Migrate fires_flutter to flutter_map v6.1.0 and complete major null-safety fixes

- Updated Android build files: gradle plugin 8.2.2, gradle 8.3, SDK 34, minSdk 21
- Ran dart fix --apply for 87 automatic null-safety fixes
- Migrated flutter_map v6 API breaking changes:
  - MapOptions: center → initialCenter, zoom → initialZoom
  - layers → children structure
  - TileLayerOptions/MarkerLayerOptions/PolylineLayerOptions → TileLayer/MarkerLayer/PolylineLayer
  - Removed plugin_api.dart imports
  - Converted old plugin system (ZoomMapPlugin, AttributionPlugin, etc.) to direct widgets
  - Updated onTap callback signature: (TapPosition) → (TapPosition, LatLng)
- Migrated all marker/polyline creation to v6 API
- Fixed FlatButton → TextButton deprecation
- Fixed stackTrace access with catch(e, stackTrace) pattern
- Removed deprecated flutter_google_places_autocomplete dependency
- Removed deprecated dependencies: latlong, connectivity, launch_review
- Updated all imports from latlong → latlong2
- Placeholder implementation for places autocomplete (feature temporarily disabled)

Remaining tasks (non-blocking for build):
- Complete null-safety fixes for _location variables in genericMap.dart
- Fix theme.dart MaterialTheme parameter issues
- Fix customStepper.dart null-safety issues
- Final build and testing

lib/fireNotificationList.dart

@@ -26,13 +26,13 @@ class _ViewModel {
   final DeleteAllFireNotificationFunction onDeleteAll;
 
   _ViewModel(
-      {@required this.isLoaded,
-      @required this.onTap,
-      @required this.onDelete,
-      @required this.onDeleteAll,
-      @required this.fireNotifications,
-      @required this.yourLocations,
-      @required this.fireNotificationsUnread});
+      {required this.isLoaded,
+      required this.onTap,
+      required this.onDelete,
+      required this.onDeleteAll,
+      required this.fireNotifications,
+      required this.yourLocations,
+      required this.fireNotificationsUnread});
 
   @override
   bool operator ==(Object other) =>
@@ -66,13 +66,11 @@ class _FireNotificationListState extends State<FireNotificationList> {
       FireNotification notif, onDeleted, onTap) {
     String prefix = "";
 
-    if (notif.subsId != null) {
-      // FIXME (this can fails if you don't have a location for this notif, for instance during tests)
-      YourLocation yl =
-          yourLocations.singleWhere((yl) => yl.id == notif.subsId);
-      prefix = '${yl.description}. ';
-    }
-
+    // FIXME (this can fails if you don't have a location for this notif, for instance during tests)
+    YourLocation yl =
+        yourLocations.singleWhere((yl) => yl.id == notif.subsId);
+    prefix = '${yl.description}. ';
+  
     return new ListTile(
         dense: true,
         leading: const Icon(Icons.whatshot),