Merge README update from remote

- 실시간 출석 현황 화면(TeacherAttendancePage)에 데스크톱(웹 브라우저 800px+) 전용
  레이아웃 추가: 통계 타일 3개 + 정식 DataTable. 교사 대시보드 메뉴 그리드도
  데스크톱에서 카드가 지나치게 커지지 않도록 최대 너비 제한
- Firebase Hosting에 웹 빌드 배포 설정 추가 (firebase.json hosting 섹션),
  https://school-display-ff28f.web.app 로 선생님이 브라우저에서 바로 접속 가능
- 무단 반출(/api/violations/active) 감지 시 대시보드에 빨간 표시 + "반출 허용" 버튼 추가
- 선생님이 개별 학생에게 N분간 반출 허용(/api/violations/allow), 또는 전체 학생에게
  한 번에 반출 허용 시간대 설정(/api/permissions/window, 쉬는시간 등) 가능하도록 연동

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

firebase.json

@@ -1 +1 @@
-{"flutter":{"platforms":{"android":{"default":{"projectId":"school-display-ff28f","appId":"1:137322214849:android:2595999513206bdeb16b40","fileOutput":"android/app/google-services.json"}},"dart":{"lib/firebase_options.dart":{"projectId":"school-display-ff28f","configurations":{"android":"1:137322214849:android:2595999513206bdeb16b40","web":"1:137322214849:web:0423e5c788d95761b16b40"}}}}}}
+{"flutter":{"platforms":{"android":{"default":{"projectId":"school-display-ff28f","appId":"1:137322214849:android:2595999513206bdeb16b40","fileOutput":"android/app/google-services.json"}},"dart":{"lib/firebase_options.dart":{"projectId":"school-display-ff28f","configurations":{"android":"1:137322214849:android:2595999513206bdeb16b40","web":"1:137322214849:web:0423e5c788d95761b16b40"}}}}},"hosting":{"public":"build/web","ignore":["firebase.json","**/.*"],"rewrites":[{"source":"**","destination":"/index.html"}]}}

lib/screens/teacher_attendance_page.dart

@@ -23,6 +23,7 @@ final RegExp _logNamePattern = RegExp(r'^(.*?)\s*\(([^)]*)\)$');
 class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
   List<dynamic> _roster = []; // 전체 학생 명단 (/api/users)
   List<dynamic> _logs = []; // 출석 로그 (/api/logs)
+  Map<String, dynamic> _activeViolationsByStudentId = {}; // 무단반출 중인 학생 (/api/violations/active)
   Timer? _timer;
   bool _isLoading = true;
   String _filterType = "ALL"; // "ALL", "CHECKED_IN", "ABSENT"
@@ -45,17 +46,29 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
       final results = await Future.wait([
         http.get(Uri.parse('$baseUrl/api/users')),
         http.get(Uri.parse('$baseUrl/api/logs')),
+        http.get(Uri.parse('$baseUrl/api/violations/active')),
       ]);
 
       final usersRes = results[0];
       final logsRes = results[1];
+      final violationsRes = results[2];
 
       if (usersRes.statusCode == 200 && logsRes.statusCode == 200) {
         final usersData = jsonDecode(utf8.decode(usersRes.bodyBytes));
         final logsData = jsonDecode(utf8.decode(logsRes.bodyBytes));
+
+        Map<String, dynamic> activeViolations = {};
+        if (violationsRes.statusCode == 200) {
+          final violationsData = jsonDecode(utf8.decode(violationsRes.bodyBytes));
+          for (final v in (violationsData['violations'] ?? [])) {
+            activeViolations[v['student_id'].toString()] = v;
+          }
+        }
+
         setState(() {
           _roster = usersData['users'] ?? [];
           _logs = logsData['logs'] ?? [];
+          _activeViolationsByStudentId = activeViolations;
           _isLoading = false;
         });
       } else {
@@ -66,6 +79,125 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
     }
   }
 
+  /// 🚨 선생님이 특정 학생에게 지금부터 N분간 반출을 허용한다.
+  Future<void> _allowRemoval(String studentId, int minutes) async {
+    try {
+      final response = await http.post(
+        Uri.parse('$baseUrl/api/violations/allow'),
+        headers: {"Content-Type": "application/json"},
+        body: jsonEncode({"studentId": studentId, "minutes": minutes}),
+      );
+      final result = jsonDecode(utf8.decode(response.bodyBytes));
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text(result['message'] ?? '처리되었습니다.')),
+      );
+      _fetchAll();
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text('❌ 반출 허용 실패: $e')),
+      );
+    }
+  }
+
+  /// ⏰ 지금부터 N분간 전체 학생의 반출을 자동으로 허용한다 (쉬는시간 등).
+  Future<void> _setPermissionWindow(int minutes) async {
+    try {
+      final response = await http.post(
+        Uri.parse('$baseUrl/api/permissions/window'),
+        headers: {"Content-Type": "application/json"},
+        body: jsonEncode({"minutes": minutes}),
+      );
+      final result = jsonDecode(utf8.decode(response.bodyBytes));
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text(result['message'] ?? '처리되었습니다.')),
+      );
+      _fetchAll();
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text('❌ 설정 실패: $e')),
+      );
+    }
+  }
+
+  void _showAllowDialog(String studentId, String studentName) {
+    final controller = TextEditingController(text: "5");
+    showDialog(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: Text('$studentName 학생 반출 허용'),
+        content: TextField(
+          controller: controller,
+          keyboardType: TextInputType.number,
+          decoration: const InputDecoration(
+            labelText: '허용 시간 (분)',
+            border: OutlineInputBorder(),
+          ),
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('취소'),
+          ),
+          ElevatedButton(
+            onPressed: () {
+              final minutes = int.tryParse(controller.text.trim()) ?? 5;
+              Navigator.pop(context);
+              _allowRemoval(studentId, minutes);
+            },
+            child: const Text('허용하기'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  void _showPermissionWindowDialog() {
+    final controller = TextEditingController(text: "10");
+    showDialog(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: const Text('⏰ 전체 학생 반출 허용 시간 설정'),
+        content: Column(
+          mainAxisSize: MainAxisSize.min,
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            const Text(
+              '쉬는시간처럼 지금부터 일정 시간 동안 모든 학생의 반출을 자동으로 허용합니다.',
+              style: TextStyle(fontSize: 13, color: Colors.grey),
+            ),
+            const SizedBox(height: 16),
+            TextField(
+              controller: controller,
+              keyboardType: TextInputType.number,
+              decoration: const InputDecoration(
+                labelText: '지금부터 허용 시간 (분)',
+                border: OutlineInputBorder(),
+              ),
+            ),
+          ],
+        ),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('취소'),
+          ),
+          ElevatedButton(
+            onPressed: () {
+              final minutes = int.tryParse(controller.text.trim()) ?? 10;
+              Navigator.pop(context);
+              _setPermissionWindow(minutes);
+            },
+            child: const Text('설정하기'),
+          ),
+        ],
+      ),
+    );
+  }
+
   /// 오늘 날짜 기준으로 학번별 "가장 최근 출석 기록"만 남긴 맵을 만든다.
   Map<String, Map<String, String>> get _todaysCheckInsByStudentId {
     final String todayPrefix = DateTime.now().toIso8601String().substring(
@@ -100,12 +232,16 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
     return _roster.map((u) {
       final String id = u['id']?.toString() ?? '';
       final checkIn = checkIns[id];
+      final violation = _activeViolationsByStudentId[id];
       return {
         'studentId': id,
         'studentName': u['name']?.toString() ?? '',
         'isCheckedIn': checkIn != null,
         'pocketNumber': checkIn?['pocketNumber'],
         'checkInTime': checkIn?['time'],
+        'hasActiveViolation': violation != null,
+        'violationPocket': violation?['pocket_number'],
+        'violationTime': violation?['time'],
       };
     }).toList();
   }
@@ -137,12 +273,38 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
         backgroundColor: Colors.blue,
         foregroundColor: Colors.white,
         elevation: 0,
+        actions: [
+          TextButton.icon(
+            onPressed: _showPermissionWindowDialog,
+            icon: const Icon(Icons.timer_outlined, color: Colors.white),
+            label: const Text(
+              '반출 허용 시간 설정',
+              style: TextStyle(color: Colors.white),
+            ),
+          ),
+          const SizedBox(width: 8),
+        ],
       ),
       body: _isLoading
           ? const Center(child: CircularProgressIndicator())
-          : Column(
+          : LayoutBuilder(
+              builder: (context, constraints) {
+                final bool isWide = constraints.maxWidth >= 800;
+                return isWide
+                    ? _buildDesktopBody(totalCount, checkedInCount, absentCount)
+                    : _buildMobileBody(totalCount, checkedInCount, absentCount);
+              },
+            ),
+    );
+  }
+
+  // -----------------------------------------------------------------------
+  // 📱 모바일 레이아웃 (기존 카드 리스트)
+  // -----------------------------------------------------------------------
+  Widget _buildMobileBody(int total, int checkedIn, int absent) {
+    return Column(
       children: [
-                _buildSummaryCards(totalCount, checkedInCount, absentCount),
+        _buildSummaryCards(total, checkedIn, absent),
         _buildFilterChips(),
         Expanded(
           child: _filteredStudents.isEmpty
@@ -158,6 +320,7 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
                   itemBuilder: (context, index) {
                     final student = _filteredStudents[index];
                     final bool isCheckedIn = student['isCheckedIn'];
+                    final bool hasViolation = student['hasActiveViolation'] == true;
                     return Container(
                       margin: const EdgeInsets.symmetric(
                         horizontal: 24,
@@ -165,8 +328,11 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
                       ),
                       padding: const EdgeInsets.all(18),
                       decoration: BoxDecoration(
-                                color: Colors.white,
+                        color: hasViolation ? Colors.red[50] : Colors.white,
                         borderRadius: BorderRadius.circular(20),
+                        border: hasViolation
+                            ? Border.all(color: Colors.red[300]!, width: 1.5)
+                            : null,
                         boxShadow: [
                           BoxShadow(
                             color: Colors.black.withValues(alpha: 0.03),
@@ -175,32 +341,36 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
                           ),
                         ],
                       ),
-                              child: Row(
+                      child: Column(
+                        crossAxisAlignment: CrossAxisAlignment.start,
+                        children: [
+                          Row(
                             children: [
                               Container(
                                 padding: const EdgeInsets.all(10),
                                 decoration: BoxDecoration(
-                                      color: (isCheckedIn
-                                              ? Colors.blue
-                                              : Colors.red)
+                                  color: (hasViolation
+                                          ? Colors.red
+                                          : (isCheckedIn ? Colors.blue : Colors.red))
                                       .withValues(alpha: 0.1),
                                   shape: BoxShape.circle,
                                 ),
                                 child: Icon(
-                                      isCheckedIn
+                                  hasViolation
+                                      ? Icons.warning_amber_rounded
+                                      : (isCheckedIn
                                           ? Icons.check_circle_rounded
-                                          : Icons.error_rounded,
-                                      color: isCheckedIn
-                                          ? Colors.blue
-                                          : Colors.red,
+                                          : Icons.error_rounded),
+                                  color: hasViolation
+                                      ? Colors.red
+                                      : (isCheckedIn ? Colors.blue : Colors.red),
                                   size: 24,
                                 ),
                               ),
                               const SizedBox(width: 16),
                               Expanded(
                                 child: Column(
-                                      crossAxisAlignment:
-                                          CrossAxisAlignment.start,
+                                  crossAxisAlignment: CrossAxisAlignment.start,
                                   children: [
                                     Text(
                                       '${student['studentName']} 학생',
@@ -211,21 +381,27 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
                                     ),
                                     const SizedBox(height: 4),
                                     Text(
-                                          isCheckedIn
+                                      hasViolation
+                                          ? '🚨 무단반출 감지! (${student['violationTime']})'
+                                          : (isCheckedIn
                                               ? '학번: ${student['studentId']} | 제출시간: ${student['checkInTime']}'
-                                              : '학번: ${student['studentId']} | 미제출',
+                                              : '학번: ${student['studentId']} | 미제출'),
                                       style: TextStyle(
-                                            color: isCheckedIn
+                                        color: hasViolation
+                                            ? Colors.red[700]
+                                            : (isCheckedIn
                                                 ? Colors.grey[600]
-                                                : Colors.red[400],
+                                                : Colors.red[400]),
                                         fontSize: 12,
+                                        fontWeight: hasViolation
+                                            ? FontWeight.bold
+                                            : FontWeight.normal,
                                       ),
                                     ),
                                   ],
                                 ),
                               ),
-                                  if (isCheckedIn &&
-                                      student['pocketNumber'] != null)
+                              if (isCheckedIn && student['pocketNumber'] != null)
                                 Container(
                                   padding: const EdgeInsets.symmetric(
                                     horizontal: 12,
@@ -234,9 +410,8 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
                                   decoration: BoxDecoration(
                                     color: Colors.blue.shade50,
                                     borderRadius: BorderRadius.circular(20),
-                                        border: Border.all(
-                                          color: Colors.blue.shade200,
-                                        ),
+                                    border:
+                                        Border.all(color: Colors.blue.shade200),
                                   ),
                                   child: Text(
                                     student['pocketNumber'],
@@ -249,11 +424,273 @@ class _TeacherAttendancePageState extends State<TeacherAttendancePage> {
                                 ),
                             ],
                           ),
+                          if (hasViolation)
+                            Padding(
+                              padding: const EdgeInsets.only(top: 12),
+                              child: SizedBox(
+                                width: double.infinity,
+                                child: ElevatedButton.icon(
+                                  onPressed: () => _showAllowDialog(
+                                    student['studentId'],
+                                    student['studentName'],
+                                  ),
+                                  icon: const Icon(Icons.check, size: 18),
+                                  label: const Text('반출 허용'),
+                                  style: ElevatedButton.styleFrom(
+                                    backgroundColor: Colors.red[600],
+                                    foregroundColor: Colors.white,
+                                  ),
+                                ),
+                              ),
+                            ),
+                        ],
+                      ),
                     );
                   },
                 ),
         ),
       ],
+    );
+  }
+
+  // -----------------------------------------------------------------------
+  // 🖥️ 데스크톱 레이아웃 (선생님이 교실 컴퓨터 브라우저로 접속했을 때)
+  // -----------------------------------------------------------------------
+  Widget _buildDesktopBody(int total, int checkedIn, int absent) {
+    return Center(
+      child: ConstrainedBox(
+        constraints: const BoxConstraints(maxWidth: 1100),
+        child: Padding(
+          padding: const EdgeInsets.all(24.0),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              Row(
+                children: [
+                  Expanded(
+                    child: _statTile(
+                      "전체 학생",
+                      "$total명",
+                      Icons.groups_rounded,
+                      Colors.blueGrey,
+                    ),
+                  ),
+                  const SizedBox(width: 16),
+                  Expanded(
+                    child: _statTile(
+                      "출석 완료",
+                      "$checkedIn명",
+                      Icons.check_circle_rounded,
+                      Colors.green,
+                    ),
+                  ),
+                  const SizedBox(width: 16),
+                  Expanded(
+                    child: _statTile(
+                      "미출석",
+                      "$absent명",
+                      Icons.error_rounded,
+                      Colors.red,
+                    ),
+                  ),
+                ],
+              ),
+              const SizedBox(height: 20),
+              _buildFilterChips(),
+              const SizedBox(height: 12),
+              Expanded(
+                child: Container(
+                  width: double.infinity,
+                  decoration: BoxDecoration(
+                    color: Colors.white,
+                    borderRadius: BorderRadius.circular(16),
+                    boxShadow: [
+                      BoxShadow(
+                        color: Colors.black.withValues(alpha: 0.04),
+                        blurRadius: 16,
+                        offset: const Offset(0, 4),
+                      ),
+                    ],
+                  ),
+                  child: _filteredStudents.isEmpty
+                      ? const Center(
+                          child: Text(
+                            '해당하는 학생이 없습니다.',
+                            style: TextStyle(color: Colors.grey),
+                          ),
+                        )
+                      : SingleChildScrollView(
+                          child: DataTable(
+                            headingRowColor: WidgetStateProperty.all(
+                              Colors.grey[50],
+                            ),
+                            columns: const [
+                              DataColumn(label: Text('상태')),
+                              DataColumn(label: Text('학번')),
+                              DataColumn(label: Text('이름')),
+                              DataColumn(label: Text('제출 시간')),
+                              DataColumn(label: Text('주머니 번호')),
+                              DataColumn(label: Text('작업')),
+                            ],
+                            rows: _filteredStudents.map((student) {
+                              final bool isCheckedIn = student['isCheckedIn'];
+                              final bool hasViolation =
+                                  student['hasActiveViolation'] == true;
+                              return DataRow(
+                                color: hasViolation
+                                    ? WidgetStateProperty.all(Colors.red[50])
+                                    : null,
+                                cells: [
+                                  DataCell(
+                                    Icon(
+                                      hasViolation
+                                          ? Icons.warning_amber_rounded
+                                          : (isCheckedIn
+                                              ? Icons.check_circle_rounded
+                                              : Icons.error_rounded),
+                                      color: hasViolation
+                                          ? Colors.red
+                                          : (isCheckedIn
+                                              ? Colors.blue
+                                              : Colors.red),
+                                      size: 20,
+                                    ),
+                                  ),
+                                  DataCell(Text('${student['studentId']}')),
+                                  DataCell(
+                                    Text(
+                                      '${student['studentName']}',
+                                      style: const TextStyle(
+                                        fontWeight: FontWeight.bold,
+                                      ),
+                                    ),
+                                  ),
+                                  DataCell(
+                                    Text(
+                                      hasViolation
+                                          ? '🚨 무단반출 (${student['violationTime']})'
+                                          : (isCheckedIn
+                                              ? '${student['checkInTime']}'
+                                              : '미제출'),
+                                      style: TextStyle(
+                                        color: hasViolation
+                                            ? Colors.red[700]
+                                            : (isCheckedIn
+                                                ? Colors.grey[700]
+                                                : Colors.red[400]),
+                                        fontWeight: hasViolation
+                                            ? FontWeight.bold
+                                            : FontWeight.normal,
+                                      ),
+                                    ),
+                                  ),
+                                  DataCell(
+                                    isCheckedIn && student['pocketNumber'] != null
+                                        ? Container(
+                                            padding: const EdgeInsets.symmetric(
+                                              horizontal: 10,
+                                              vertical: 4,
+                                            ),
+                                            decoration: BoxDecoration(
+                                              color: Colors.blue.shade50,
+                                              borderRadius:
+                                                  BorderRadius.circular(20),
+                                              border: Border.all(
+                                                color: Colors.blue.shade200,
+                                              ),
+                                            ),
+                                            child: Text(
+                                              student['pocketNumber'],
+                                              style: const TextStyle(
+                                                fontWeight: FontWeight.bold,
+                                                color: Colors.blueAccent,
+                                                fontSize: 12,
+                                              ),
+                                            ),
+                                          )
+                                        : const Text('-'),
+                                  ),
+                                  DataCell(
+                                    hasViolation
+                                        ? ElevatedButton.icon(
+                                            onPressed: () => _showAllowDialog(
+                                              student['studentId'],
+                                              student['studentName'],
+                                            ),
+                                            icon: const Icon(
+                                              Icons.check,
+                                              size: 16,
+                                            ),
+                                            label: const Text('반출 허용'),
+                                            style: ElevatedButton.styleFrom(
+                                              backgroundColor: Colors.red[600],
+                                              foregroundColor: Colors.white,
+                                              padding:
+                                                  const EdgeInsets.symmetric(
+                                                horizontal: 12,
+                                              ),
+                                            ),
+                                          )
+                                        : const Text('-'),
+                                  ),
+                                ],
+                              );
+                            }).toList(),
+                          ),
+                        ),
+                ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _statTile(String label, String value, IconData icon, Color color) {
+    return Container(
+      padding: const EdgeInsets.all(20),
+      decoration: BoxDecoration(
+        color: Colors.white,
+        borderRadius: BorderRadius.circular(16),
+        boxShadow: [
+          BoxShadow(
+            color: Colors.black.withValues(alpha: 0.04),
+            blurRadius: 12,
+            offset: const Offset(0, 4),
+          ),
+        ],
+      ),
+      child: Row(
+        children: [
+          Container(
+            padding: const EdgeInsets.all(12),
+            decoration: BoxDecoration(
+              color: color.withValues(alpha: 0.1),
+              borderRadius: BorderRadius.circular(12),
+            ),
+            child: Icon(icon, color: color, size: 26),
+          ),
+          const SizedBox(width: 14),
+          Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              Text(
+                label,
+                style: TextStyle(color: Colors.grey[600], fontSize: 13),
+              ),
+              const SizedBox(height: 2),
+              Text(
+                value,
+                style: TextStyle(
+                  color: color,
+                  fontSize: 22,
+                  fontWeight: FontWeight.bold,
+                ),
+              ),
+            ],
+          ),
+        ],
       ),
     );
   }

lib/screens/teacher_dashboard.dart

@@ -135,7 +135,11 @@ class _TeacherDashboardState extends State<TeacherDashboard> {
             const SizedBox(height: 16),
 
             // 📊 [그리드 레이아웃 메뉴] 시후의 카드 컴포넌트 스타일 적용
-            Padding(
+            // 🖥️ 데스크톱 브라우저에서 카드가 지나치게 커지지 않도록 최대 너비를 제한한다.
+            Center(
+              child: ConstrainedBox(
+                constraints: const BoxConstraints(maxWidth: 700),
+                child: Padding(
                   padding: const EdgeInsets.symmetric(horizontal: 24.0),
                   child: GridView.count(
                     shrinkWrap: true,
@@ -173,6 +177,8 @@ class _TeacherDashboardState extends State<TeacherDashboard> {
                     ],
                   ),
                 ),
+              ),
+            ),
             const SizedBox(height: 32),
           ],
         ),