feat: Add geocoding functionality for trips and enhance activity search with coordinates

lib/blocs/activity/activity_event.dart

@@ -43,6 +43,32 @@ class SearchActivities extends ActivityEvent {
   List<Object?> get props => [tripId, destination, category, maxResults, offset, reset, appendToExisting];
 }
 
+/// Event to search activities using coordinates directly (bypasses geocoding)
+class SearchActivitiesWithCoordinates extends ActivityEvent {
+  final String tripId;
+  final double latitude;
+  final double longitude;
+  final ActivityCategory? category;
+  final int? maxResults;
+  final int? offset;
+  final bool reset;
+  final bool appendToExisting;
+
+  const SearchActivitiesWithCoordinates({
+    required this.tripId,
+    required this.latitude,
+    required this.longitude,
+    this.category,
+    this.maxResults,
+    this.offset,
+    this.reset = false,
+    this.appendToExisting = false,
+  });
+
+  @override
+  List<Object?> get props => [tripId, latitude, longitude, category, maxResults, offset, reset, appendToExisting];
+}
+
 /// Event to search activities by text query
 class SearchActivitiesByText extends ActivityEvent {
   final String tripId;