대시보드 배너/타이틀 중앙정렬 + 타일 UI 편집(드래그 이동/크기조절) + 로그인 유지 기능 추가

- 이름/부제, "스마트 관리 시스템 메뉴" 제목을 중앙 정렬
- 타일을 1x1~4x4 크기로 자유 배치할 수 있는 편집 모드 추가 (6x4 캔버스, 삼성 One UI 위젯 편집 방식)
- 타일 배치는 계정별로 서버에 저장/복원 (dashboard_layout_controller.dart)
- 설정 화면(톱니바퀴 아이콘) > "UI 편집" 진입점 추가
- shared_preferences로 로그인 유지 기능 추가 (비밀번호는 저장하지 않음)

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

lib/debug_pocket_main.dart

@@ -13,10 +13,7 @@ class DebugPocketApp extends StatelessWidget {
   Widget build(BuildContext context) {
     return const MaterialApp(
       debugShowCheckedModeBanner: false,
-      home: NfcPocketCheckInScreen(
-        studentId: "2061",
-        studentName: "디버그테스트",
-      ),
+      home: NfcPocketCheckInScreen(studentId: "2061", studentName: "디버그테스트"),
     );
   }
 }

lib/function/dashboard_layout_controller.dart

@@ -0,0 +1,158 @@
+// 🧩 대시보드 타일 배치(위치/크기)의 서버 통신/상태 담당 컨트롤러.
+// 캔버스는 6열×4행 고정, 타일 크기는 1x1~4x4. 계정별로 서버(계정=userId)에 저장한다.
+import 'dart:convert';
+import 'package:flutter/foundation.dart';
+import 'package:http/http.dart' as http;
+import '../config.dart';
+import '../models/dashboard_tile_layout.dart';
+
+class DashboardLayoutController extends ChangeNotifier {
+  final String userId;
+  DashboardLayoutController(this.userId);
+
+  Map<String, TileRect> _positions = {};
+  bool _isLoading = true;
+  bool _isSaving = false;
+  bool _isEditing = false;
+
+  Map<String, TileRect> get positions => _positions;
+  bool get isLoading => _isLoading;
+  bool get isSaving => _isSaving;
+  bool get isEditing => _isEditing;
+
+  void enterEditMode() {
+    _isEditing = true;
+    notifyListeners();
+  }
+
+  /// 편집 중이던 변경을 서버에 저장하지 않고 그대로 유지한 채 편집 모드만 끈다.
+  /// (저장은 [save]를 명시적으로 불러야 함 — 완료 버튼이 save+exit를 같이 호출한다.)
+  void exitEditMode() {
+    _isEditing = false;
+    notifyListeners();
+  }
+
+  /// 서버에 저장된 배치를 불러오고, 현재 화면에 보여야 할 타일 id 목록([visibleIds]) 중
+  /// 저장된 값이 없는 새 타일은 빈 칸을 찾아 1x1로 자동 배치한다.
+  Future<void> load(List<String> visibleIds) async {
+    _isLoading = true;
+    notifyListeners();
+
+    Map<String, TileRect> loaded = {};
+    try {
+      final response = await http.get(
+        Uri.parse('$baseUrl/api/dashboard/layout?userId=$userId'),
+      );
+      if (response.statusCode == 200) {
+        final data = jsonDecode(utf8.decode(response.bodyBytes));
+        final rawLayout = data['layout'];
+        if (rawLayout is List) {
+          for (final item in rawLayout) {
+            final id = item['id']?.toString();
+            if (id == null) continue;
+            final rect = TileRect.fromJson(item);
+            if (rect.isWithinCanvas) loaded[id] = rect;
+          }
+        }
+      }
+    } catch (_) {
+      // 새로고침 실패는 조용히 무시하고 기본 배치로 대체한다.
+    }
+
+    _positions = _fillDefaults(loaded, visibleIds);
+    _isLoading = false;
+    notifyListeners();
+  }
+
+  Map<String, TileRect> _fillDefaults(
+    Map<String, TileRect> existing,
+    List<String> ids,
+  ) {
+    final Map<String, TileRect> result = {};
+    for (final id in ids) {
+      final saved = existing[id];
+      if (saved != null && !_collidesWithAny(result, saved, null)) {
+        result[id] = saved;
+      }
+    }
+    for (final id in ids) {
+      if (result.containsKey(id)) continue;
+      final spot = _findFirstFit(result, 1, 1);
+      if (spot != null) {
+        result[id] = TileRect(x: spot.$1, y: spot.$2, w: 1, h: 1);
+      }
+      // 캔버스(6x4=24칸)가 꽉 찼으면 자리를 못 찾을 수도 있음 — 그 타일은 화면에 안 보이게 됨.
+    }
+    return result;
+  }
+
+  bool _collidesWithAny(
+    Map<String, TileRect> placed,
+    TileRect candidate,
+    String? ignoreId,
+  ) {
+    for (final entry in placed.entries) {
+      if (entry.key == ignoreId) continue;
+      if (entry.value.overlaps(candidate)) return true;
+    }
+    return false;
+  }
+
+  (int, int)? _findFirstFit(Map<String, TileRect> placed, int w, int h) {
+    for (int y = 0; y <= kGridRows - h; y++) {
+      for (int x = 0; x <= kGridCols - w; x++) {
+        final candidate = TileRect(x: x, y: y, w: w, h: h);
+        if (!_collidesWithAny(placed, candidate, null)) return (x, y);
+      }
+    }
+    return null;
+  }
+
+  bool _fits(String movingId, TileRect candidate) {
+    if (!candidate.isWithinCanvas) return false;
+    return !_collidesWithAny(_positions, candidate, movingId);
+  }
+
+  /// 타일을 (newX, newY)로 옮긴다. 다른 타일과 겹치거나 캔버스를 벗어나면 무시하고 false 반환.
+  bool tryMove(String id, int newX, int newY) {
+    final cur = _positions[id];
+    if (cur == null) return false;
+    final candidate = cur.copyWith(x: newX, y: newY);
+    if (!_fits(id, candidate)) return false;
+    _positions = {..._positions, id: candidate};
+    notifyListeners();
+    return true;
+  }
+
+  /// 타일 크기를 (newW, newH)로 바꾼다. 다른 타일과 겹치거나 4x4/캔버스를 벗어나면 무시.
+  bool tryResize(String id, int newW, int newH) {
+    final cur = _positions[id];
+    if (cur == null) return false;
+    final candidate = cur.copyWith(w: newW, h: newH);
+    if (!_fits(id, candidate)) return false;
+    _positions = {..._positions, id: candidate};
+    notifyListeners();
+    return true;
+  }
+
+  Future<void> save() async {
+    _isSaving = true;
+    notifyListeners();
+    try {
+      final layout = _positions.entries
+          .map((e) => e.value.toJson(e.key))
+          .toList();
+      await http.post(
+        Uri.parse('$baseUrl/api/dashboard/layout'),
+        headers: {"Content-Type": "application/json"},
+        body: jsonEncode({"userId": userId, "layout": layout}),
+      );
+    } catch (_) {
+      // 저장 실패해도 로컬 배치는 유지 — 다음에 다시 시도 가능.
+    } finally {
+      _isSaving = false;
+      _isEditing = false;
+      notifyListeners();
+    }
+  }
+}

lib/function/session_store.dart

@@ -0,0 +1,66 @@
+// 🔐 "로그인 유지" 기능. 로그인 성공 시 계정 정보를 기기에 저장해두고,
+// 다음 실행 때 로그인 화면을 건너뛰고 바로 대시보드로 들어가게 한다.
+// (서버에 별도 세션/토큰 개념이 없어서, 비밀번호는 저장하지 않고 신원 정보만 저장한다.)
+import 'dart:convert';
+import 'package:shared_preferences/shared_preferences.dart';
+
+class SavedSession {
+  final String userId;
+  final String userName;
+  final String role;
+  final bool isDeviceMatched;
+
+  const SavedSession({
+    required this.userId,
+    required this.userName,
+    required this.role,
+    required this.isDeviceMatched,
+  });
+
+  Map<String, dynamic> toJson() => {
+    'userId': userId,
+    'userName': userName,
+    'role': role,
+    'isDeviceMatched': isDeviceMatched,
+  };
+
+  factory SavedSession.fromJson(Map<String, dynamic> json) => SavedSession(
+    userId: json['userId'] as String,
+    userName: json['userName'] as String,
+    role: json['role'] as String,
+    isDeviceMatched: json['isDeviceMatched'] as bool? ?? true,
+  );
+}
+
+class SessionStore {
+  static const _key = 'saved_session_v1';
+
+  static Future<void> save(SavedSession session) async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      await prefs.setString(_key, jsonEncode(session.toJson()));
+    } catch (_) {
+      // 저장 실패해도 로그인 자체는 계속 진행 (로그인 유지만 안 될 뿐).
+    }
+  }
+
+  static Future<SavedSession?> load() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      final raw = prefs.getString(_key);
+      if (raw == null) return null;
+      return SavedSession.fromJson(jsonDecode(raw));
+    } catch (_) {
+      return null;
+    }
+  }
+
+  static Future<void> clear() async {
+    try {
+      final prefs = await SharedPreferences.getInstance();
+      await prefs.remove(_key);
+    } catch (_) {
+      // 무시 - 어차피 로그아웃 화면으로는 이동한다.
+    }
+  }
+}

lib/main_client_app.dart

@@ -6,9 +6,11 @@ import 'package:flutter/material.dart';
 import 'package:firebase_core/firebase_core.dart';
 import 'firebase_options.dart';
 import 'config.dart';
+import 'function/session_store.dart';
 import 'pocket_watch_service.dart';
 import 'theme/app_palette.dart';
 import 'ui/login_screen.dart';
+import 'ui/main_dashboard.dart';
 
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
@@ -44,7 +46,56 @@ class SchoolAttendanceApp extends StatelessWidget {
               onSurface: AppPalette.ink,
             ),
       ),
-      home: const LoginScreen(), // 🚪 앱을 켜면 무조건 로그인 화면이 먼저 등장합니다.
+      home: const _StartupGate(), // 🚪 저장된 로그인이 있으면 대시보드로, 없으면 로그인 화면으로.
     );
   }
 }
+
+/// 🔐 "로그인 유지" 진입점. 기기에 저장된 세션이 있는지 확인하는 동안 잠깐 로딩을 보여주고,
+/// 있으면 로그인 화면 없이 바로 대시보드로, 없으면 로그인 화면으로 보낸다.
+class _StartupGate extends StatefulWidget {
+  const _StartupGate();
+
+  @override
+  State<_StartupGate> createState() => _StartupGateState();
+}
+
+class _StartupGateState extends State<_StartupGate> {
+  SavedSession? _session;
+  bool _checked = false;
+
+  @override
+  void initState() {
+    super.initState();
+    _checkSession();
+  }
+
+  Future<void> _checkSession() async {
+    final session = await SessionStore.load();
+    if (!mounted) return;
+    setState(() {
+      _session = session;
+      _checked = true;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    if (!_checked) {
+      return Scaffold(
+        backgroundColor: AppPalette.mist,
+        body: const Center(child: CircularProgressIndicator()),
+      );
+    }
+    final session = _session;
+    if (session != null) {
+      return MainDashboard(
+        userId: session.userId,
+        userName: session.userName,
+        role: session.role,
+        isDeviceMatched: session.isDeviceMatched,
+      );
+    }
+    return const LoginScreen();
+  }
+}

lib/models/dashboard_tile_layout.dart

@@ -0,0 +1,55 @@
+// 🧩 대시보드 타일의 격자 위치/크기(1x1 ~ 4x4)를 표현하는 값 객체.
+// 전체 배치 캔버스는 가로 6칸 × 세로 4칸으로 고정한다.
+const int kGridCols = 6;
+const int kGridRows = 4;
+const int kMinTileSize = 1;
+const int kMaxTileSize = 4;
+
+class TileRect {
+  final int x;
+  final int y;
+  final int w;
+  final int h;
+
+  const TileRect({
+    required this.x,
+    required this.y,
+    required this.w,
+    required this.h,
+  });
+
+  factory TileRect.fromJson(Map<String, dynamic> json) => TileRect(
+    x: (json['x'] as num).toInt(),
+    y: (json['y'] as num).toInt(),
+    w: (json['w'] as num).toInt(),
+    h: (json['h'] as num).toInt(),
+  );
+
+  Map<String, dynamic> toJson(String id) => {
+    'id': id,
+    'x': x,
+    'y': y,
+    'w': w,
+    'h': h,
+  };
+
+  TileRect copyWith({int? x, int? y, int? w, int? h}) =>
+      TileRect(x: x ?? this.x, y: y ?? this.y, w: w ?? this.w, h: h ?? this.h);
+
+  bool overlaps(TileRect other) {
+    return x < other.x + other.w &&
+        x + w > other.x &&
+        y < other.y + other.h &&
+        y + h > other.y;
+  }
+
+  bool get isWithinCanvas =>
+      x >= 0 &&
+      y >= 0 &&
+      x + w <= kGridCols &&
+      y + h <= kGridRows &&
+      w >= kMinTileSize &&
+      h >= kMinTileSize &&
+      w <= kMaxTileSize &&
+      h <= kMaxTileSize;
+}

lib/ui/dashboard_settings_page.dart

@@ -0,0 +1,49 @@
+// ⚙️ 대시보드 설정 화면 (UI 전용). 지금은 "UI 편집" 진입점 하나만 있다.
+// "UI 편집"을 누르면 이 화면을 pop('edit_ui')로 닫고, 대시보드가 그 결과를 받아 편집 모드로 들어간다.
+import 'package:flutter/material.dart';
+import '../theme/app_palette.dart';
+
+class DashboardSettingsPage extends StatelessWidget {
+  const DashboardSettingsPage({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      backgroundColor: AppPalette.mist,
+      appBar: AppBar(
+        title: const Text('설정'),
+        backgroundColor: AppPalette.ink,
+        foregroundColor: AppPalette.paper,
+        elevation: 0,
+      ),
+      body: ListView(
+        padding: const EdgeInsets.all(16),
+        children: [
+          Container(
+            decoration: BoxDecoration(
+              color: AppPalette.paper,
+              borderRadius: BorderRadius.circular(16),
+              border: Border.all(color: AppPalette.sage),
+            ),
+            child: ListTile(
+              shape: RoundedRectangleBorder(
+                borderRadius: BorderRadius.circular(16),
+              ),
+              leading: const Icon(
+                Icons.grid_view_rounded,
+                color: AppPalette.ink,
+              ),
+              title: const Text(
+                'UI 편집',
+                style: TextStyle(fontWeight: FontWeight.bold),
+              ),
+              subtitle: const Text('타일을 드래그해서 옮기고 크기를 바꿀 수 있어요.'),
+              trailing: const Icon(Icons.chevron_right_rounded),
+              onTap: () => Navigator.pop(context, 'edit_ui'),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/ui/login_screen.dart

@@ -3,6 +3,7 @@
 import 'package:flutter/material.dart';
 import '../config.dart' show schoolName;
 import '../function/login_controller.dart';
+import '../function/session_store.dart';
 import '../theme/app_palette.dart';
 import 'main_dashboard.dart';
 import 'teacher_register_screen.dart';
@@ -43,6 +44,15 @@ class _LoginScreenState extends State<LoginScreen> {
         _showErrorDialog(result.errorMessage!);
         break;
       case LoginOutcome.masterSuccess:
+        await SessionStore.save(
+          SavedSession(
+            userId: result.studentId!,
+            userName: result.name!,
+            role: 'student',
+            isDeviceMatched: true,
+          ),
+        );
+        if (!mounted) return;
         ScaffoldMessenger.of(
           context,
         ).showSnackBar(const SnackBar(content: Text('개발자 최고 권한으로 로그인되었습니다.')));
@@ -178,12 +188,21 @@ class _LoginScreenState extends State<LoginScreen> {
   }
 
   // 🆕 권한별 화면 이동시 기기 일치 여부 파라미터(`isDeviceMatched`) 수신 및 대시보드 전달
-  void _navigateBasedOnRole(
+  Future<void> _navigateBasedOnRole(
     String role,
     String studentId,
     String name,
     bool isDeviceMatched,
-  ) {
+  ) async {
+    await SessionStore.save(
+      SavedSession(
+        userId: studentId,
+        userName: name,
+        role: role,
+        isDeviceMatched: isDeviceMatched,
+      ),
+    );
+    if (!mounted) return;
     Navigator.pushReplacement(
       context,
       MaterialPageRoute(

lib/ui/main_dashboard.dart

@@ -1,11 +1,16 @@
 // 🏠 통합 대시보드 (UI 전용). 학생/교사/관리자가 전부 이 화면 하나를 공유하고,
 // 권한(role)에 따라 배너 색상/문구와 보이는 타일만 달라진다.
-// 레이아웃(그리드, 카드 디자인)을 한 곳에서 고치면 모든 역할에 동시에 적용된다.
-// 계정 강제 삭제 서버 통신은 lib/function/student_dashboard_controller.dart가 담당한다.
+// 타일 배치(위치/크기)는 사용자가 직접 편집할 수 있고, 계정별로 서버에 저장된다
+// (lib/function/dashboard_layout_controller.dart). 캔버스는 가로 6칸×세로 4칸,
+// 타일 크기는 1x1~4x4.
 import 'package:flutter/material.dart';
+import '../function/dashboard_layout_controller.dart';
+import '../function/session_store.dart';
 import '../function/student_dashboard_controller.dart';
+import '../models/dashboard_tile_layout.dart';
 import '../theme/app_palette.dart';
 import 'admin_dashboard.dart';
+import 'dashboard_settings_page.dart';
 import 'device_checkout_ledger_page.dart';
 import 'device_checkout_request_screen.dart';
 import 'login_screen.dart';
@@ -34,6 +39,11 @@ class MainDashboard extends StatefulWidget {
 
 class _MainDashboardState extends State<MainDashboard> {
   final StudentDashboardController _controller = StudentDashboardController();
+  late final DashboardLayoutController _layout;
+
+  // 🎯 타일 이동/크기조절 드래그 중 기준값(드래그 시작 시점의 좌표)을 담아둔다.
+  Offset? _dragStartGlobal;
+  TileRect? _dragStartRect;
 
   // 🔑 [권한 판정] 2061은 role이 'student'로 저장돼 있지만 실질적으로 최고 권한을 가진다.
   bool get _isDeveloper => widget.userId == '2061';
@@ -46,9 +56,17 @@ class _MainDashboardState extends State<MainDashboard> {
   String get _displayName =>
       widget.userName ?? (widget.role == 'admin' ? '시스템 관리자' : '간편인증 선생');
 
+  @override
+  void initState() {
+    super.initState();
+    _layout = DashboardLayoutController(_displayId);
+    _layout.load(_tileSpecs().map((t) => t.id).toList());
+  }
+
   @override
   void dispose() {
     _controller.dispose();
+    _layout.dispose();
     super.dispose();
   }
 
@@ -161,6 +179,25 @@ class _MainDashboardState extends State<MainDashboard> {
     );
   }
 
+  Future<void> _logout(BuildContext context) async {
+    await SessionStore.clear();
+    if (!context.mounted) return;
+    Navigator.pushReplacement(
+      context,
+      MaterialPageRoute(builder: (context) => const LoginScreen()),
+    );
+  }
+
+  Future<void> _openSettings(BuildContext context) async {
+    final result = await Navigator.push<String>(
+      context,
+      MaterialPageRoute(builder: (context) => const DashboardSettingsPage()),
+    );
+    if (result == 'edit_ui') {
+      _layout.enterEditMode();
+    }
+  }
+
   // 🎨 [역할별 테마] 배너 색상은 팔레트로 통일하고, 제목/문구/아이콘만 역할에 따라 다르게.
   ({String title, String subtitle, Color color, IconData icon}) _theme() {
     if (_isDeveloper) {
@@ -193,12 +230,210 @@ class _MainDashboardState extends State<MainDashboard> {
     );
   }
 
+  // 🧩 역할에 따라 보이는 타일 목록. id는 서버 레이아웃 저장의 키로 쓰이므로 절대 바뀌면 안 된다.
+  List<({String id, Widget child})> _tileSpecs() {
+    final List<({String id, Widget child})> tiles = [];
+
+    if (_isStudent) {
+      tiles.add((
+        id: 'nfc_tag',
+        child: _buildModernCard(
+          icon: widget.isDeviceMatched
+              ? Icons.contactless_rounded
+              : Icons.lock_rounded,
+          title: 'NFC 태그',
+          subtitle: widget.isDeviceMatched ? '출석 및 폰 수거 완료' : '본인 인증 기기 전용',
+          color: widget.isDeviceMatched ? AppPalette.ink : AppPalette.sage,
+          onTap: widget.isDeviceMatched
+              ? () => _openPocketCheckIn(context)
+              : () {
+                  ScaffoldMessenger.of(context).showSnackBar(
+                    const SnackBar(
+                      content: Text('대리 출석 방지를 위해 등록된 본인 스마트폰에서만 출석 가능합니다.'),
+                    ),
+                  );
+                },
+          isActionButton: widget.isDeviceMatched,
+          isLoading: _controller.isLoading,
+        ),
+      ));
+      tiles.add((
+        id: 'school_status',
+        child: _buildModernCard(
+          icon: Icons.fastfood_rounded,
+          title: '실시간 학교 상황',
+          subtitle: '급식실 줄 & 매점 재고 확인',
+          color: AppPalette.ink,
+          onTap: () {
+            ScaffoldMessenger.of(context).showSnackBar(
+              const SnackBar(content: Text('실시간 학교 상황 페이지로 이동합니다.')),
+            );
+          },
+        ),
+      ));
+      tiles.add((
+        id: 'device_checkout_request',
+        child: _buildModernCard(
+          icon: Icons.tablet_mac_rounded,
+          title: '스마트기기 반출',
+          subtitle: '패드 사용 신청 (시간/목적)',
+          color: AppPalette.ink,
+          onTap: () => Navigator.push(
+            context,
+            MaterialPageRoute(
+              builder: (context) => DeviceCheckoutRequestScreen(
+                studentId: _displayId,
+                studentName: _displayName,
+              ),
+            ),
+          ),
+        ),
+      ));
+    }
+
+    if (_isTeacherOrAbove) {
+      tiles.add((
+        id: 'attendance_check',
+        child: _buildModernCard(
+          icon: Icons.assignment_turned_in_rounded,
+          title: '실시간 출석 확인',
+          subtitle: '학생 제출 로그 모니터링',
+          color: AppPalette.ink,
+          onTap: () => Navigator.push(
+            context,
+            MaterialPageRoute(
+              builder: (context) => const TeacherAttendancePage(),
+            ),
+          ),
+        ),
+      ));
+      tiles.add((
+        id: 'student_management',
+        child: _buildModernCard(
+          icon: Icons.manage_accounts_rounded,
+          title: '학생 계정 관리',
+          subtitle: '계정 추가 및 강제 리셋',
+          color: AppPalette.ink,
+          onTap: () => Navigator.push(
+            context,
+            MaterialPageRoute(
+              builder: (context) => const TeacherStudentManagementPage(),
+            ),
+          ),
+        ),
+      ));
+      tiles.add((
+        id: 'device_checkout_ledger',
+        child: _buildModernCard(
+          icon: Icons.tablet_mac_rounded,
+          title: '스마트기기 반출 대장',
+          subtitle: '패드 반출 신청 승인/거절',
+          color: AppPalette.ink,
+          onTap: () => Navigator.push(
+            context,
+            MaterialPageRoute(
+              builder: (context) => DeviceCheckoutLedgerPage(
+                teacherId: widget.userId,
+                teacherName: widget.userName,
+              ),
+            ),
+          ),
+        ),
+      ));
+    }
+
+    if (_isAdmin) {
+      tiles.add((
+        id: 'admin_db',
+        child: _buildModernCard(
+          icon: Icons.terminal_rounded,
+          title: '서버 DB 제어',
+          subtitle: '시스템 원격 초기화',
+          color: AppPalette.ink,
+          onTap: () => Navigator.push(
+            context,
+            MaterialPageRoute(builder: (context) => const AdminDashboard()),
+          ),
+        ),
+      ));
+      tiles.add((
+        id: 'delete_account',
+        child: _buildModernCard(
+          icon: Icons.delete_sweep_rounded,
+          title: '계정 강제 삭제',
+          subtitle: '학생 및 교사 DB 삭제',
+          color: AppPalette.ink,
+          onTap: () => _showDeleteUserDialog(context),
+        ),
+      ));
+      tiles.add((
+        id: 'nfc_tag_writer',
+        child: _buildModernCard(
+          icon: Icons.edit_note_rounded,
+          title: 'NFC 태그 쓰기',
+          subtitle: '주머니 스티커 초기 설정',
+          color: AppPalette.ink,
+          onTap: () => Navigator.push(
+            context,
+            MaterialPageRoute(builder: (context) => const NfcTagWriterScreen()),
+          ),
+        ),
+      ));
+    }
+
+    return tiles;
+  }
+
+  // ─────────────────────────────────────────────────────────
+  // 🖐️ 편집 모드: 드래그로 이동, 모서리 손잡이로 크기 조절 (1x1~4x4).
+  // ─────────────────────────────────────────────────────────
+  void _onMovePanStart(String id, DragStartDetails details) {
+    _dragStartGlobal = details.globalPosition;
+    _dragStartRect = _layout.positions[id];
+  }
+
+  void _onMovePanUpdate(String id, double cellSize, DragUpdateDetails details) {
+    if (_dragStartGlobal == null || _dragStartRect == null) return;
+    final delta = details.globalPosition - _dragStartGlobal!;
+    final dx = (delta.dx / cellSize).round();
+    final dy = (delta.dy / cellSize).round();
+    _layout.tryMove(id, _dragStartRect!.x + dx, _dragStartRect!.y + dy);
+  }
+
+  void _onMovePanEnd(DragEndDetails details) {
+    _dragStartGlobal = null;
+    _dragStartRect = null;
+  }
+
+  void _onResizePanStart(String id, DragStartDetails details) {
+    _dragStartGlobal = details.globalPosition;
+    _dragStartRect = _layout.positions[id];
+  }
+
+  void _onResizePanUpdate(
+    String id,
+    double cellSize,
+    DragUpdateDetails details,
+  ) {
+    if (_dragStartGlobal == null || _dragStartRect == null) return;
+    final delta = details.globalPosition - _dragStartGlobal!;
+    final dw = (delta.dx / cellSize).round();
+    final dh = (delta.dy / cellSize).round();
+    _layout.tryResize(id, _dragStartRect!.w + dw, _dragStartRect!.h + dh);
+  }
+
+  Future<void> _saveAndExitEdit() async {
+    await _layout.save();
+  }
+
   @override
   Widget build(BuildContext context) {
     return ListenableBuilder(
-      listenable: _controller,
+      listenable: Listenable.merge([_controller, _layout]),
       builder: (context, _) {
         final theme = _theme();
+        final tiles = _tileSpecs();
+        final bool isEditing = _layout.isEditing;
 
         return Scaffold(
           backgroundColor: AppPalette.mist,
@@ -214,17 +449,46 @@ class _MainDashboardState extends State<MainDashboard> {
             backgroundColor: theme.color,
             foregroundColor: Colors.white,
             elevation: 0,
-            actions: [
+            actions: isEditing
+                ? [
+                    TextButton.icon(
+                      onPressed: _layout.isSaving ? null : _saveAndExitEdit,
+                      icon: _layout.isSaving
+                          ? const SizedBox(
+                              width: 16,
+                              height: 16,
+                              child: CircularProgressIndicator(
+                                strokeWidth: 2,
+                                color: Colors.white,
+                              ),
+                            )
+                          : const Icon(
+                              Icons.check_rounded,
+                              color: Colors.white,
+                            ),
+                      label: const Text(
+                        '완료',
+                        style: TextStyle(color: Colors.white),
+                      ),
+                    ),
+                  ]
+                : [
+                    IconButton(
+                      icon: const Icon(Icons.settings_outlined),
+                      tooltip: '설정',
+                      onPressed: () => _openSettings(context),
+                    ),
                     IconButton(
                       icon: const Icon(Icons.logout_rounded),
-                onPressed: () => Navigator.pushReplacement(
-                  context,
-                  MaterialPageRoute(builder: (context) => const LoginScreen()),
-                ),
+                      tooltip: '로그아웃',
+                      onPressed: () => _logout(context),
                     ),
                   ],
           ),
           body: SingleChildScrollView(
+            physics: isEditing
+                ? const NeverScrollableScrollPhysics()
+                : const AlwaysScrollableScrollPhysics(),
             child: Column(
               crossAxisAlignment: CrossAxisAlignment.start,
               children: [
@@ -241,7 +505,7 @@ class _MainDashboardState extends State<MainDashboard> {
                       bottomRight: Radius.circular(32),
                     ),
                   ),
-                  child: Row(
+                  child: Column(
                     children: [
                       Container(
                         padding: const EdgeInsets.all(4),
@@ -255,12 +519,10 @@ class _MainDashboardState extends State<MainDashboard> {
                           child: Icon(theme.icon, size: 32, color: theme.color),
                         ),
                       ),
-                      const SizedBox(width: 18),
-                      Column(
-                        crossAxisAlignment: CrossAxisAlignment.start,
-                        children: [
+                      const SizedBox(height: 14),
                       Text(
                         '$_displayName 님',
+                        textAlign: TextAlign.center,
                         style: const TextStyle(
                           fontSize: 22,
                           fontWeight: FontWeight.bold,
@@ -270,6 +532,7 @@ class _MainDashboardState extends State<MainDashboard> {
                       const SizedBox(height: 4),
                       Text(
                         theme.subtitle,
+                        textAlign: TextAlign.center,
                         style: TextStyle(
                           color: Colors.white.withValues(alpha: 0.8),
                           fontSize: 14,
@@ -277,13 +540,12 @@ class _MainDashboardState extends State<MainDashboard> {
                       ),
                     ],
                   ),
-                    ],
-                  ),
                 ),
                 const SizedBox(height: 32),
                 Padding(
                   padding: const EdgeInsets.symmetric(horizontal: 24.0),
                   child: Row(
+                    mainAxisAlignment: MainAxisAlignment.center,
                     children: [
                       Container(
                         width: 4,
@@ -305,178 +567,22 @@ class _MainDashboardState extends State<MainDashboard> {
                     ],
                   ),
                 ),
+                if (isEditing)
+                  const Padding(
+                    padding: EdgeInsets.only(top: 8, left: 24, right: 24),
+                    child: Text(
+                      '타일을 드래그해서 옮기고, 오른쪽 아래 손잡이로 크기를 바꿔보세요.',
+                      textAlign: TextAlign.center,
+                      style: TextStyle(color: AppPalette.sage, fontSize: 12),
+                    ),
+                  ),
                 const SizedBox(height: 16),
-                LayoutBuilder(
-                  builder: (context, constraints) {
-                    // 🖥️ 웹(넓은 화면)은 한 줄에 5개씩, 폰(좁은 화면)은 기존 2개 그대로.
-                    final bool isWide = constraints.maxWidth >= 800;
-                    return Center(
-                      child: ConstrainedBox(
-                        constraints: BoxConstraints(
-                          maxWidth: isWide ? 1300 : 700,
-                        ),
-                        child: Padding(
-                          padding: const EdgeInsets.symmetric(horizontal: 24.0),
-                          child: GridView.count(
-                            shrinkWrap: true,
-                            physics: const NeverScrollableScrollPhysics(),
-                            crossAxisCount: isWide ? 5 : 2,
-                            crossAxisSpacing: 16,
-                            mainAxisSpacing: 16,
-                            childAspectRatio: 0.95,
-                            children: [
-                              // 👨‍🎓 학생 전용 -----------------------------------
-                              if (_isStudent)
-                                _buildModernCard(
-                                  icon: widget.isDeviceMatched
-                                      ? Icons.contactless_rounded
-                                      : Icons.lock_rounded,
-                                  title: 'NFC 태그',
-                                  subtitle: widget.isDeviceMatched
-                                      ? '출석 및 폰 수거 완료'
-                                      : '본인 인증 기기 전용',
-                                  color: widget.isDeviceMatched
-                                      ? AppPalette.ink
-                                      : AppPalette.sage,
-                                  onTap: widget.isDeviceMatched
-                                      ? () => _openPocketCheckIn(context)
-                                      : () {
-                                          ScaffoldMessenger.of(
-                                            context,
-                                          ).showSnackBar(
-                                            const SnackBar(
-                                              content: Text(
-                                                '대리 출석 방지를 위해 등록된 본인 스마트폰에서만 출석 가능합니다.',
-                                              ),
-                                            ),
-                                          );
-                                        },
-                                  isActionButton: widget.isDeviceMatched,
-                                  isLoading: _controller.isLoading,
-                                ),
-                              if (_isStudent)
-                                _buildModernCard(
-                                  icon: Icons.fastfood_rounded,
-                                  title: '실시간 학교 상황',
-                                  subtitle: '급식실 줄 & 매점 재고 확인',
-                                  color: AppPalette.ink,
-                                  onTap: () {
-                                    ScaffoldMessenger.of(context).showSnackBar(
-                                      const SnackBar(
-                                        content: Text('실시간 학교 상황 페이지로 이동합니다.'),
-                                      ),
-                                    );
-                                  },
-                                ),
-                              if (_isStudent)
-                                _buildModernCard(
-                                  icon: Icons.tablet_mac_rounded,
-                                  title: '스마트기기 반출',
-                                  subtitle: '패드 사용 신청 (시간/목적)',
-                                  color: AppPalette.ink,
-                                  onTap: () => Navigator.push(
-                                    context,
-                                    MaterialPageRoute(
-                                      builder: (context) =>
-                                          DeviceCheckoutRequestScreen(
-                                            studentId: _displayId,
-                                            studentName: _displayName,
-                                          ),
-                                    ),
-                                  ),
-                                ),
-
-                              // 👨‍🏫 교사 이상 -----------------------------------
-                              if (_isTeacherOrAbove)
-                                _buildModernCard(
-                                  icon: Icons.assignment_turned_in_rounded,
-                                  title: '실시간 출석 확인',
-                                  subtitle: '학생 제출 로그 모니터링',
-                                  color: AppPalette.ink,
-                                  onTap: () => Navigator.push(
-                                    context,
-                                    MaterialPageRoute(
-                                      builder: (context) =>
-                                          const TeacherAttendancePage(),
-                                    ),
-                                  ),
-                                ),
-                              if (_isTeacherOrAbove)
-                                _buildModernCard(
-                                  icon: Icons.manage_accounts_rounded,
-                                  title: '학생 계정 관리',
-                                  subtitle: '계정 추가 및 강제 리셋',
-                                  color: AppPalette.ink,
-                                  onTap: () => Navigator.push(
-                                    context,
-                                    MaterialPageRoute(
-                                      builder: (context) =>
-                                          const TeacherStudentManagementPage(),
-                                    ),
-                                  ),
-                                ),
-                              if (_isTeacherOrAbove)
-                                _buildModernCard(
-                                  icon: Icons.tablet_mac_rounded,
-                                  title: '스마트기기 반출 대장',
-                                  subtitle: '패드 반출 신청 승인/거절',
-                                  color: AppPalette.ink,
-                                  onTap: () => Navigator.push(
-                                    context,
-                                    MaterialPageRoute(
-                                      builder: (context) =>
-                                          DeviceCheckoutLedgerPage(
-                                            teacherId: widget.userId,
-                                            teacherName: widget.userName,
-                                          ),
-                                    ),
-                                  ),
-                                ),
-
-                              // 🛠️ 관리자 전용 -----------------------------------
-                              if (_isAdmin)
-                                _buildModernCard(
-                                  icon: Icons.terminal_rounded,
-                                  title: '서버 DB 제어',
-                                  subtitle: '시스템 원격 초기화',
-                                  color: AppPalette.ink,
-                                  onTap: () => Navigator.push(
-                                    context,
-                                    MaterialPageRoute(
-                                      builder: (context) =>
-                                          const AdminDashboard(),
-                                    ),
-                                  ),
-                                ),
-                              if (_isAdmin)
-                                _buildModernCard(
-                                  icon: Icons.delete_sweep_rounded,
-                                  title: '계정 강제 삭제',
-                                  subtitle: '학생 및 교사 DB 삭제',
-                                  color: AppPalette.ink,
-                                  onTap: () => _showDeleteUserDialog(context),
-                                ),
-                              if (_isAdmin)
-                                _buildModernCard(
-                                  icon: Icons.edit_note_rounded,
-                                  title: 'NFC 태그 쓰기',
-                                  subtitle: '주머니 스티커 초기 설정',
-                                  color: AppPalette.ink,
-                                  onTap: () => Navigator.push(
-                                    context,
-                                    MaterialPageRoute(
-                                      builder: (context) =>
-                                          const NfcTagWriterScreen(),
-                                    ),
-                                  ),
-                                ),
-                            ],
-                          ),
-                        ),
-                      ),
-                    );
-                  },
-                ),
+                _layout.isLoading
+                    ? const Padding(
+                        padding: EdgeInsets.symmetric(vertical: 40),
+                        child: Center(child: CircularProgressIndicator()),
+                      )
+                    : _buildGridCanvas(tiles, isEditing),
                 const SizedBox(height: 32),
               ],
             ),
@@ -486,7 +592,103 @@ class _MainDashboardState extends State<MainDashboard> {
     );
   }
 
-  // 💎 [카드 디자인 위젯] 학생/교사 대시보드에서 쓰던 것과 동일 — 이제 한 곳에만 존재.
+  Widget _buildGridCanvas(
+    List<({String id, Widget child})> tiles,
+    bool isEditing,
+  ) {
+    const double gap = 10;
+    const double maxCanvasWidth = 720;
+
+    return LayoutBuilder(
+      builder: (context, constraints) {
+        final double canvasWidth = constraints.maxWidth < maxCanvasWidth
+            ? constraints.maxWidth - 24
+            : maxCanvasWidth;
+        final double cellSize = canvasWidth / kGridCols;
+        final double canvasHeight = cellSize * kGridRows;
+
+        final List<Widget> positioned = [];
+        for (final tile in tiles) {
+          final rect = _layout.positions[tile.id];
+          if (rect == null) continue; // 캔버스가 꽉 차서 자리를 못 찾은 타일
+
+          final double left = rect.x * cellSize;
+          final double top = rect.y * cellSize;
+          final double w = rect.w * cellSize - gap;
+          final double h = rect.h * cellSize - gap;
+
+          positioned.add(
+            Positioned(
+              key: ValueKey(tile.id),
+              left: left,
+              top: top,
+              width: w,
+              height: h,
+              child: Stack(
+                clipBehavior: Clip.none,
+                children: [
+                  Positioned.fill(
+                    child: IgnorePointer(
+                      ignoring: isEditing,
+                      child: tile.child,
+                    ),
+                  ),
+                  if (isEditing)
+                    Positioned.fill(
+                      child: GestureDetector(
+                        behavior: HitTestBehavior.translucent,
+                        onPanStart: (d) => _onMovePanStart(tile.id, d),
+                        onPanUpdate: (d) =>
+                            _onMovePanUpdate(tile.id, cellSize, d),
+                        onPanEnd: _onMovePanEnd,
+                      ),
+                    ),
+                  if (isEditing)
+                    Positioned(
+                      right: 2,
+                      bottom: 2,
+                      child: GestureDetector(
+                        onPanStart: (d) => _onResizePanStart(tile.id, d),
+                        onPanUpdate: (d) =>
+                            _onResizePanUpdate(tile.id, cellSize, d),
+                        onPanEnd: _onMovePanEnd,
+                        child: Container(
+                          width: 26,
+                          height: 26,
+                          decoration: BoxDecoration(
+                            color: AppPalette.ink,
+                            borderRadius: BorderRadius.circular(8),
+                            border: Border.all(
+                              color: AppPalette.paper,
+                              width: 2,
+                            ),
+                          ),
+                          child: const Icon(
+                            Icons.open_in_full_rounded,
+                            size: 14,
+                            color: AppPalette.paper,
+                          ),
+                        ),
+                      ),
+                    ),
+                ],
+              ),
+            ),
+          );
+        }
+
+        return Center(
+          child: SizedBox(
+            width: canvasWidth,
+            height: canvasHeight,
+            child: Stack(children: positioned),
+          ),
+        );
+      },
+    );
+  }
+
+  // 💎 [카드 디자인 위젯] 타일 크기가 커지면 아이콘/글자도 비례해서 커진다.
   Widget _buildModernCard({
     required IconData icon,
     required String title,
@@ -496,14 +698,26 @@ class _MainDashboardState extends State<MainDashboard> {
     bool isActionButton = false,
     bool isLoading = false,
   }) {
+    return LayoutBuilder(
+      builder: (context, constraints) {
+        // 📏 타일의 실제 픽셀 크기를 기준으로 배율을 계산 (1x1 기준 ≈ 1.0).
+        final double scale = (constraints.maxWidth / 110).clamp(1.0, 3.4);
+        final double iconBoxPadding = 6 + 6 * (scale - 1);
+        final double iconSize = 16 + 10 * (scale - 1);
+        final double iconRadius = 10 + 6 * (scale - 1);
+        final double cardPadding = 8 + 8 * (scale - 1);
+        final double cardRadius = 16 + 6 * (scale - 1);
+        final double titleFontSize = (10 + 3 * (scale - 1)).clamp(10, 18);
+        final double subtitleFontSize = (8 + 2 * (scale - 1)).clamp(8, 14);
+
         return InkWell(
           onTap: isLoading ? null : onTap,
-      borderRadius: BorderRadius.circular(24),
+          borderRadius: BorderRadius.circular(cardRadius),
           child: Ink(
-        padding: const EdgeInsets.all(20),
+            padding: EdgeInsets.all(cardPadding),
             decoration: BoxDecoration(
               color: AppPalette.paper,
-          borderRadius: BorderRadius.circular(24),
+              borderRadius: BorderRadius.circular(cardRadius),
               border: Border.all(color: AppPalette.sage, width: 1),
             ),
             child: Column(
@@ -511,12 +725,12 @@ class _MainDashboardState extends State<MainDashboard> {
               mainAxisAlignment: MainAxisAlignment.spaceBetween,
               children: [
                 Container(
-              padding: const EdgeInsets.all(12),
+                  padding: EdgeInsets.all(iconBoxPadding),
                   decoration: BoxDecoration(
                     color: AppPalette.linen,
-                borderRadius: BorderRadius.circular(16),
+                    borderRadius: BorderRadius.circular(iconRadius),
                   ),
-              child: Icon(icon, color: color, size: 28),
+                  child: Icon(icon, color: color, size: iconSize),
                 ),
                 Column(
                   crossAxisAlignment: CrossAxisAlignment.start,
@@ -527,8 +741,10 @@ class _MainDashboardState extends State<MainDashboard> {
                         Expanded(
                           child: Text(
                             title,
-                        style: const TextStyle(
-                          fontSize: 15,
+                            maxLines: 2,
+                            overflow: TextOverflow.ellipsis,
+                            style: TextStyle(
+                              fontSize: titleFontSize,
                               fontWeight: FontWeight.bold,
                               color: AppPalette.ink,
                             ),
@@ -536,25 +752,27 @@ class _MainDashboardState extends State<MainDashboard> {
                         ),
                         if (isLoading)
                           const SizedBox(
-                        width: 16,
-                        height: 16,
+                            width: 14,
+                            height: 14,
                             child: CircularProgressIndicator(strokeWidth: 2),
                           )
                         else if (isActionButton)
                           Icon(
                             Icons.touch_app_rounded,
-                        size: 16,
+                            size: 14,
                             color: color.withValues(alpha: 0.5),
                           ),
                       ],
                     ),
-                const SizedBox(height: 4),
+                    SizedBox(height: 1 + 2 * (scale - 1)),
                     Text(
                       subtitle,
+                      maxLines: 2,
+                      overflow: TextOverflow.ellipsis,
                       style: TextStyle(
-                    fontSize: 12,
+                        fontSize: subtitleFontSize,
                         color: AppPalette.ink.withValues(alpha: 0.55),
-                    height: 1.2,
+                        height: 1.15,
                       ),
                     ),
                   ],
@@ -563,5 +781,7 @@ class _MainDashboardState extends State<MainDashboard> {
             ),
           ),
         );
+      },
+    );
   }
 }

macos/Flutter/GeneratedPluginRegistrant.swift

@@ -11,6 +11,7 @@ import file_picker_darwin
 import firebase_core
 import firebase_messaging
 import flutter_local_notifications
+import shared_preferences_foundation
 
 func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   DesktopDropPlugin.register(with: registry.registrar(forPlugin: "DesktopDropPlugin"))
@@ -19,4 +20,5 @@ func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   FLTFirebaseCorePlugin.register(with: registry.registrar(forPlugin: "FLTFirebaseCorePlugin"))
   FLTFirebaseMessagingPlugin.register(with: registry.registrar(forPlugin: "FLTFirebaseMessagingPlugin"))
   FlutterLocalNotificationsPlugin.register(with: registry.registrar(forPlugin: "FlutterLocalNotificationsPlugin"))
+  SharedPreferencesPlugin.register(with: registry.registrar(forPlugin: "SharedPreferencesPlugin"))
 }

pubspec.lock

@@ -472,6 +472,30 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.9.1"
+  path_provider_linux:
+    dependency: transitive
+    description:
+      name: path_provider_linux
+      sha256: "58c2005f147315b11e9b4a7bc889cd5203e250cba8e3f012dae259b4972b5c16"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.2"
+  path_provider_platform_interface:
+    dependency: transitive
+    description:
+      name: path_provider_platform_interface
+      sha256: "484838772624c3a4b94f1e44a3e19897fee738f2d5c4ce448443b0417f7c9dda"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.3"
+  path_provider_windows:
+    dependency: transitive
+    description:
+      name: path_provider_windows
+      sha256: bd6f00dbd873bfb70d0761682da2b3a2c2fccc2b9e84c495821639601d81afe7
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.0"
   permission_handler:
     dependency: "direct main"
     description:
@@ -544,6 +568,62 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.8"
+  shared_preferences:
+    dependency: "direct main"
+    description:
+      name: shared_preferences
+      sha256: c3025c5534b01739267eb7d76959bbc25a6d10f6988e1c2a3036940133dd10bf
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.5"
+  shared_preferences_android:
+    dependency: transitive
+    description:
+      name: shared_preferences_android
+      sha256: "1e12aafe408aa50da80edfd679a2a6bf63ba7ab37c7fa98286da459a757b3399"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.28"
+  shared_preferences_foundation:
+    dependency: transitive
+    description:
+      name: shared_preferences_foundation
+      sha256: "2ec3934efa51e46117f23031cc141b8fc878e8525b94ec1ea4f7f586cf1b47ea"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.5.7"
+  shared_preferences_linux:
+    dependency: transitive
+    description:
+      name: shared_preferences_linux
+      sha256: "580abfd40f415611503cae30adf626e6656dfb2f0cee8f465ece7b6defb40f2f"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
+  shared_preferences_platform_interface:
+    dependency: transitive
+    description:
+      name: shared_preferences_platform_interface
+      sha256: "649dc798a33931919ea356c4305c2d1f81619ea6e92244070b520187b5140ef9"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.2"
+  shared_preferences_web:
+    dependency: transitive
+    description:
+      name: shared_preferences_web
+      sha256: c49bd060261c9a3f0ff445892695d6212ff603ef3115edbb448509d407600019
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.3"
+  shared_preferences_windows:
+    dependency: transitive
+    description:
+      name: shared_preferences_windows
+      sha256: "94ef0f72b2d71bc3e700e025db3710911bd51a71cefb65cc609dd0d9a982e3c1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.4.1"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -703,4 +783,4 @@ packages:
     version: "6.6.1"
 sdks:
   dart: ">=3.12.2 <4.0.0"
-  flutter: ">=3.41.0"
+  flutter: ">=3.44.0"

pubspec.yaml

@@ -41,6 +41,7 @@ dependencies:
   nfc_manager: ^4.2.1
   nfc_manager_ndef: ^1.1.0
   http: ^1.1.0
+  shared_preferences: ^2.3.3
 
   # 🔦 주머니 제출 모드 무단 반출 감지용 조도 센서 (Android 전용, iOS는 SensorKit 엔타이틀먼트 필요)
   light: ^5.0.0