fix: enhance missing Google Maps API key error message with debug details including available keys and platform information.

lib/services/activity_places_service.dart

@@ -116,7 +116,15 @@ class ActivityPlacesService {
         LoggerService.error(
           'ActivityPlacesService: Clé API Google Maps manquante',
         );
-        throw Exception('Clé API Google Maps non configurée');
+        // Debug: Lister les clés disponibles pour comprendre le problème
+        final availableKeys = dotenv.env.keys.join(', ');
+        throw Exception(
+          'Clé API Google Maps non configurée. Clés disponibles: [$availableKeys]. Platform: ${Platform.isAndroid
+              ? 'Android'
+              : Platform.isIOS
+              ? 'iOS'
+              : 'Autre'}',
+        );
       }
 
       final encodedDestination = Uri.encodeComponent(destination);