feat: Implement activity management feature with Firestore integration

- Added AddActivityBottomSheet for adding custom activities to trips.
- Created Activity model to represent tourist activities.
- Developed ActivityRepository for managing activities in Firestore.
- Integrated ActivityPlacesService for searching activities via Google Places API.
- Updated ShowTripDetailsContent to navigate to activities page.
- Enhanced main.dart to include ActivityBloc and necessary repositories.

lib/components/home/show_trip_details_content.dart

@@ -6,6 +6,7 @@ import 'package:travel_mate/components/home/create_trip_content.dart';
 import 'package:travel_mate/models/trip.dart';
 import 'package:travel_mate/components/map/map_content.dart';
 import 'package:travel_mate/services/error_service.dart';
+import 'package:travel_mate/components/activities/activities_page.dart';
 import 'package:url_launcher/url_launcher.dart';
 
 class ShowTripDetailsContent extends StatefulWidget {
@@ -402,7 +403,7 @@ class _ShowTripDetailsContentState extends State<ShowTripDetailsContent> {
                         icon: Icons.local_activity,
                         title: 'Activités',
                         color: Colors.green,
-                        onTap: () => _showComingSoon('Activités'),
+                        onTap: () => _navigateToActivities(),
                       ),
                       _buildActionButton(
                         icon: Icons.account_balance_wallet,
@@ -624,4 +625,13 @@ class _ShowTripDetailsContentState extends State<ShowTripDetailsContent> {
       ),
     );
   }
+
+  void _navigateToActivities() {
+    Navigator.push(
+      context,
+      MaterialPageRoute(
+        builder: (context) => ActivitiesPage(trip: widget.trip),
+      ),
+    );
+  }
 }