feat: Implement background location tracking service

- Removed existing app icons from the asset catalog.
- Added new `Contents.json` for asset catalog.
- Updated `Info.plist` to include background modes and task scheduler identifiers.
- Exposed BLE service in `ConnectionProvider` for background tracking.
- Enhanced `MapTab` to support background location tracking with new service.
- Added `BackgroundLocationService` to manage location updates in the background.
- Updated `SettingsScreen` to allow users to configure GPS update distance and toggle background tracking.
- Implemented functionality to send location updates via BLE in `MeshCoreBleService`.
- Updated dependencies in `pubspec.yaml` for background service support.
- Adjusted `TileCacheService` to ensure ObjectBox is initialized only once.

macos/Podfile.lock

@@ -1,42 +1,74 @@
 PODS:
+  - file_picker (0.0.1):
+    - FlutterMacOS
   - flutter_blue_plus_darwin (0.0.2):
     - Flutter
     - FlutterMacOS
   - FlutterMacOS (1.0.0)
-  - ObjectBox (1.9.2)
+  - geolocator_apple (1.2.0):
+    - Flutter
+    - FlutterMacOS
+  - ObjectBox (4.4.1)
   - objectbox_flutter_libs (0.0.1):
     - FlutterMacOS
-    - ObjectBox (= 1.9.2)
+    - ObjectBox (= 4.4.1)
+  - package_info_plus (0.0.1):
+    - FlutterMacOS
   - path_provider_foundation (0.0.1):
     - Flutter
     - FlutterMacOS
+  - share_plus (0.0.1):
+    - FlutterMacOS
+  - shared_preferences_foundation (0.0.1):
+    - Flutter
+    - FlutterMacOS
 
 DEPENDENCIES:
+  - file_picker (from `Flutter/ephemeral/.symlinks/plugins/file_picker/macos`)
   - flutter_blue_plus_darwin (from `Flutter/ephemeral/.symlinks/plugins/flutter_blue_plus_darwin/darwin`)
   - FlutterMacOS (from `Flutter/ephemeral`)
+  - geolocator_apple (from `Flutter/ephemeral/.symlinks/plugins/geolocator_apple/darwin`)
   - objectbox_flutter_libs (from `Flutter/ephemeral/.symlinks/plugins/objectbox_flutter_libs/macos`)
+  - package_info_plus (from `Flutter/ephemeral/.symlinks/plugins/package_info_plus/macos`)
   - path_provider_foundation (from `Flutter/ephemeral/.symlinks/plugins/path_provider_foundation/darwin`)
+  - share_plus (from `Flutter/ephemeral/.symlinks/plugins/share_plus/macos`)
+  - shared_preferences_foundation (from `Flutter/ephemeral/.symlinks/plugins/shared_preferences_foundation/darwin`)
 
 SPEC REPOS:
   trunk:
     - ObjectBox
 
 EXTERNAL SOURCES:
+  file_picker:
+    :path: Flutter/ephemeral/.symlinks/plugins/file_picker/macos
   flutter_blue_plus_darwin:
     :path: Flutter/ephemeral/.symlinks/plugins/flutter_blue_plus_darwin/darwin
   FlutterMacOS:
     :path: Flutter/ephemeral
+  geolocator_apple:
+    :path: Flutter/ephemeral/.symlinks/plugins/geolocator_apple/darwin
   objectbox_flutter_libs:
     :path: Flutter/ephemeral/.symlinks/plugins/objectbox_flutter_libs/macos
+  package_info_plus:
+    :path: Flutter/ephemeral/.symlinks/plugins/package_info_plus/macos
   path_provider_foundation:
     :path: Flutter/ephemeral/.symlinks/plugins/path_provider_foundation/darwin
+  share_plus:
+    :path: Flutter/ephemeral/.symlinks/plugins/share_plus/macos
+  shared_preferences_foundation:
+    :path: Flutter/ephemeral/.symlinks/plugins/shared_preferences_foundation/darwin
 
 SPEC CHECKSUMS:
+  file_picker: 7584aae6fa07a041af2b36a2655122d42f578c1a
   flutter_blue_plus_darwin: 20a08bfeaa0f7804d524858d3d8744bcc1b6dbc3
   FlutterMacOS: d0db08ddef1a9af05a5ec4b724367152bb0500b1
-  ObjectBox: 46757a559717ab49b1cc0612eaff82b705acf394
-  objectbox_flutter_libs: ac606b51011c9ea99c0574bf2db0d27b053c750a
+  geolocator_apple: ab36aa0e8b7d7a2d7639b3b4e48308394e8cef5e
+  ObjectBox: 7da4aceb5013d041bfafdbc6d744a26918b09757
+  objectbox_flutter_libs: f51d18f6a4b5965c218843373b7dc5ed5e3a2008
+  package_info_plus: f0052d280d17aa382b932f399edf32507174e870
   path_provider_foundation: 080d55be775b7414fd5a5ef3ac137b97b097e564
+  share_plus: 510bf0af1a42cd602274b4629920c9649c52f4cc
+  shared_preferences_foundation: 9e1978ff2562383bd5676f64ec4e9aa8fa06a6f7
 
 PODFILE CHECKSUM: 54d867c82ac51cbd61b565781b9fada492027009