claude refactorings, flutter best practices, platform dependent changes, general cleanup

lib/api/marianumcloud/talk/actions/talk_actions.dart

@@ -1,8 +1,8 @@
 import 'package:http/http.dart' as http;
 
-import '../../../apiParams.dart';
-import '../../../apiResponse.dart';
-import '../talkApi.dart';
+import '../../../api_params.dart';
+import '../../../api_response.dart';
+import '../talk_api.dart';
 
 /// Small POST/DELETE-only Talk endpoints that have no response payload.
 /// Each class extends [TalkApi] with `assemble` returning `null`. They share