refactor(calendar): remove deprecated reminder components

apps/lib/core/di/injection.dart

@@ -20,7 +20,6 @@ import '../../features/calendar/data/calendar_api.dart';
 import '../../features/calendar/data/services/calendar_repository.dart';
 import '../../features/calendar/data/services/calendar_service.dart';
 import '../../features/calendar/reminders/reminder_action_executor.dart';
-import '../../features/calendar/reminders/reminder_outbox_store.dart';
 import '../../features/calendar/ui/calendar_state_manager.dart';
 import '../../features/friends/data/friends_api.dart';
 import '../../features/messages/data/inbox_api.dart';
@@ -98,15 +97,11 @@ Future<void> configureDependencies() async {
   );
   sl.registerSingleton<CalendarRepository>(calendarRepository);
 
-  final reminderOutboxStore = ReminderOutboxStore(sharedPreferences);
-  sl.registerSingleton<ReminderOutboxStore>(reminderOutboxStore);
-
   sl.registerSingleton<LocalNotificationService>(LocalNotificationService());
 
   final reminderActionExecutor = ReminderActionExecutor(
     calendarService: calendarService,
     notificationService: sl<LocalNotificationService>(),
-    outboxStore: reminderOutboxStore,
   );
   sl.registerSingleton<ReminderActionExecutor>(reminderActionExecutor);