Add Next.js admin panel and implement background worker jobs

- Add full Next.js admin panel with:
  - User, residence, task, contractor, document management
  - Notifications and notification preferences management
  - Subscriptions and auth token management
  - Dashboard with stats
  - Lookup tables management (categories, priorities, statuses, etc.)
  - Admin user management

- Implement background worker job handlers:
  - HandleTaskReminder: sends push notifications for tasks due within 24h
  - HandleOverdueReminder: sends push notifications for overdue tasks
  - HandleDailyDigest: sends daily summary of pending tasks
  - HandleSendEmail: processes email sending jobs
  - HandleSendPush: processes push notification jobs

- Make worker job schedules configurable via environment variables:
  - TASK_REMINDER_HOUR, TASK_REMINDER_MINUTE (default: 20:00 UTC)
  - OVERDUE_REMINDER_HOUR (default: 09:00 UTC)
  - DAILY_DIGEST_HOUR (default: 11:00 UTC)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

.gitignore

@@ -7,7 +7,8 @@
 bin/
 api
 worker
-admin
+/admin
+!admin/
 *.exe
 *.exe~
 *.dll