test(03-01): add failing tests for DailyPlanDao cross-room query and completion count

- 7 failing tests for watchAllTasksWithRoomName and watchCompletionsToday
- DAO stub with UnimplementedError methods registered in AppDatabase
- TaskWithRoom and DailyPlanState model classes defined

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/core/database/database.dart

@@ -2,6 +2,7 @@ import 'package:drift/drift.dart';
 import 'package:drift_flutter/drift_flutter.dart';
 import 'package:path_provider/path_provider.dart';
 
+import '../../features/home/data/daily_plan_dao.dart';
 import '../../features/rooms/data/rooms_dao.dart';
 import '../../features/tasks/data/tasks_dao.dart';
 import '../../features/tasks/domain/effort_level.dart';
@@ -44,7 +45,7 @@ class TaskCompletions extends Table {
 
 @DriftDatabase(
   tables: [Rooms, Tasks, TaskCompletions],
-  daos: [RoomsDao, TasksDao],
+  daos: [RoomsDao, TasksDao, DailyPlanDao],
 )
 class AppDatabase extends _$AppDatabase {
   AppDatabase([QueryExecutor? executor])

lib/core/database/database.g.dart

@@ -1245,6 +1245,7 @@ abstract class _$AppDatabase extends GeneratedDatabase {
   );
   late final RoomsDao roomsDao = RoomsDao(this as AppDatabase);
   late final TasksDao tasksDao = TasksDao(this as AppDatabase);
+  late final DailyPlanDao dailyPlanDao = DailyPlanDao(this as AppDatabase);
   @override
   Iterable<TableInfo<Table, Object?>> get allTables =>
       allSchemaEntities.whereType<TableInfo<Table, Object?>>();