feat(api,ui,db): add address, guest users, image URLs; update API

- Backend:
  - Add address column to tickets and migration script
  - Create guest users when user_id is missing; accept user_name and address
  - Normalize stored image paths and expose absolute image_url
  - Introduce utils for path normalization and ticket serialization
  - Add CORS configuration for dashboard/emulator origins
  - Tickets API:
    - Serialize via ticket_to_dict with consistent schema
    - Change status update to PATCH /api/tickets/{id}/status with JSON body
    - Add DELETE /api/tickets/{id} with safe file removal
- Dashboard:
  - Fetch tickets from backend, show thumbnails, absolute image URLs
  - Status select + PATCH updates, toasts for feedback
  - Add i18n key btn.viewDetails
- Mobile app:
  - Persist device user_id via SharedPreferences
  - Fetch and merge API tickets; prefer network imageUrl
  - Submit user_name and address; delete via API when available
  - Make location acquisition robust with fallbacks and non-blocking UX
- Android/deps:
  - Disable Geolocator NMEA listener to prevent crashes
  - Downgrade geolocator to ^11.0.0 for stability

BREAKING CHANGE:
- Status endpoint changed from PATCH /api/tickets/{id}?new_status=... to
  PATCH /api/tickets/{id}/status with JSON body: {"status":"in_progress"}.
- /api/tickets and /api/tickets/{id} responses now use "id" (replacing
  "ticket_id"), include "image_url", and normalize fields for clients. Update
  consumers to use the new schema.

pubspec.yaml

@@ -36,7 +36,7 @@ dependencies:
   flutter_map: ^8.2.2
   flutter_map_marker_cluster: ^8.2.2
   latlong2: ^0.9.1
-  geolocator: ^12.0.0
+  geolocator: ^11.0.0
   image_picker: ^1.1.2
   path_provider: ^2.1.4
   shared_preferences: ^2.3.2