refactor(server): tags (#2589)

* refactor: tags

* chore: open api

* chore: unused import

* feat: add/remove/get tag assets

* chore: open api

* chore: finish tag tests for add/remove assets

mobile/openapi/test/asset_ids_dto_test.dart

@@ -0,0 +1,27 @@
+//
+// AUTO-GENERATED FILE, DO NOT MODIFY!
+//
+// @dart=2.12
+
+// ignore_for_file: unused_element, unused_import
+// ignore_for_file: always_put_required_named_parameters_first
+// ignore_for_file: constant_identifier_names
+// ignore_for_file: lines_longer_than_80_chars
+
+import 'package:openapi/api.dart';
+import 'package:test/test.dart';
+
+// tests for AssetIdsDto
+void main() {
+  // final instance = AssetIdsDto();
+
+  group('test AssetIdsDto', () {
+    // List<String> assetIds (default value: const [])
+    test('to test the property `assetIds`', () async {
+      // TODO
+    });
+
+
+  });
+
+}