feat(08-01): add isActive filters to CalendarDao, DailyPlanDao, RoomsDao

- CalendarDao: filter all 6 task queries (watchTasksForDate,
  watchTasksForDateInRoom, watchOverdueTasks, watchOverdueTasksInRoom,
  getTaskCount, getTaskCountInRoom) by isActive=true
- DailyPlanDao: filter all 3 queries (watchAllTasksWithRoomName,
  getOverdueAndTodayTaskCount, getOverdueTaskCount) by isActive=true
- RoomsDao: filter watchRoomWithStats task query by isActive=true
- Update migration test: add schema_v3.dart, test v1->v3 and v2->v3 paths
- Update database_test schemaVersion assertion to expect 3
- Fix test helpers in home_screen_test and task_list_screen_test to pass isActive=true

lib/features/rooms/data/rooms_dao.dart

@@ -44,7 +44,9 @@ class RoomsDao extends DatabaseAccessor<AppDatabase> with _$RoomsDaoMixin {
       final stats = <RoomWithStats>[];
       for (final room in roomList) {
         final taskList = await (select(tasks)
-              ..where((t) => t.roomId.equals(room.id)))
+              ..where(
+                (t) => t.roomId.equals(room.id) & t.isActive.equals(true),
+              ))
             .get();
 
         final totalTasks = taskList.length;