refactor(apps): 主题系统迁移至 ColorScheme + 扩展架构并支持 Dark Mode

apps/lib/data/repositories/models/calendar_event.dart

@@ -0,0 +1,40 @@
+enum CalendarEventStatus { active, archived }
+
+class CalendarEvent {
+  final String id;
+  final String title;
+  final DateTime startAt;
+  final DateTime? endAt;
+  final CalendarEventStatus status;
+
+  const CalendarEvent({
+    required this.id,
+    required this.title,
+    required this.startAt,
+    required this.endAt,
+    required this.status,
+  });
+
+  factory CalendarEvent.fromJson(Map<String, dynamic> json) {
+    return CalendarEvent(
+      id: json['id'] as String,
+      title: json['title'] as String,
+      startAt: DateTime.parse(json['start_at'] as String).toLocal(),
+      endAt: json['end_at'] == null
+          ? null
+          : DateTime.parse(json['end_at'] as String).toLocal(),
+      status: _calendarEventStatusFromApi(json['status'] as String),
+    );
+  }
+}
+
+CalendarEventStatus _calendarEventStatusFromApi(String raw) {
+  switch (raw) {
+    case 'active':
+      return CalendarEventStatus.active;
+    case 'archived':
+      return CalendarEventStatus.archived;
+    default:
+      throw StateError('Unsupported calendar event status: $raw');
+  }
+}