Remove info-level lint issues: avoid_dynamic_calls, use_build_context_synchronously, avoid_print, non_constant_identifier_names

- Type dynamic map accesses properly (avoid_dynamic_calls in genericMap, globalFiresBottomStats)
- Capture context before async gaps (use_build_context_synchronously in genericMap, genericMapBottom, globalFiresBottomStats)
- Replace print() with debugPrint() (avoid_print in firesApi.dart)
- Rename fireMarker function and _LayerSelectorButton to camelCase
- Rename variable FireNotifications to fireNotifications
- Fix no_default_cases in switch statements (add missing subscriptionConfirm case)
- Make FireNotification fields final, remove @immutable from YourLocation (mutable)
- Make monitoredAreas field final in _ViewModel
- Update subscribeViaApi to use copyWith instead of direct field assignment

lib/models/fireNotification.dart

@@ -23,7 +23,7 @@ class FireNotification {
   factory FireNotification.fromJson(Map<String, dynamic> json) =>
       _$FireNotificationFromJson(json);
   @JsonKey(toJson: objectIdToJson, fromJson: objectIdFromJson)
-  ObjectId id;
+  final ObjectId id;
   final double lat;
   final double lon;
   final String description;