simplify: dedupe boilerplate and remove dead code across all layers

lib/api/marianumconnect/queries/get_breakers/get_breakers.dart

@@ -7,8 +7,6 @@ import 'get_breakers_response.dart';
 class GetBreakers extends MarianumConnectQuery {
   GetBreakers({super.dio});
 
-  Future<GetBreakersResponse> run() => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(endpoint('breaker'));
-    return GetBreakersResponse.fromJson(response.data!);
-  });
+  Future<GetBreakersResponse> run() =>
+      getObject('breaker', GetBreakersResponse.fromJson);
 }