implemented _performWebSocketFetchLibrariesForHotReload

Author: jyameo

dwds/lib/data/fetch_libraries_for_hot_reload_request.dart

@@ -0,0 +1,25 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fetch_libraries_for_hot_reload_request;
+
+import 'package:built_value/built_value.dart';
+import 'package:built_value/serializer.dart';
+
+part 'fetch_libraries_for_hot_reload_request.g.dart';
+
+/// A request to fetch libraries for hot reload.
+abstract class FetchLibrariesForHotReloadRequest
+    implements Built<FetchLibrariesForHotReloadRequest, FetchLibrariesForHotReloadRequestBuilder> {
+  static Serializer<FetchLibrariesForHotReloadRequest> get serializer =>
+      _$fetchLibrariesForHotReloadRequestSerializer;
+
+  /// A unique identifier for this request.
+  String get id;
+
+  FetchLibrariesForHotReloadRequest._();
+  factory FetchLibrariesForHotReloadRequest([
+    void Function(FetchLibrariesForHotReloadRequestBuilder) updates,
+  ]) = _$FetchLibrariesForHotReloadRequest;
+}

dwds/lib/data/fetch_libraries_for_hot_reload_request.g.dart

@@ -0,0 +1,32 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library fetch_libraries_for_hot_reload_response;
+
+import 'package:built_value/built_value.dart';
+import 'package:built_value/serializer.dart';
+
+part 'fetch_libraries_for_hot_reload_response.g.dart';
+
+/// A response to a fetch libraries for hot reload request.
+abstract class FetchLibrariesForHotReloadResponse
+    implements Built<FetchLibrariesForHotReloadResponse, FetchLibrariesForHotReloadResponseBuilder> {
+  static Serializer<FetchLibrariesForHotReloadResponse> get serializer =>
+      _$fetchLibrariesForHotReloadResponseSerializer;
+
+  /// The unique identifier matching the request.
+  String get id;
+
+  /// Whether the fetch succeeded on the client.
+  bool get success;
+
+  /// An optional error message if success is false.
+  @BuiltValueField(wireName: 'error')
+  String? get errorMessage;
+
+  FetchLibrariesForHotReloadResponse._();
+  factory FetchLibrariesForHotReloadResponse([
+    void Function(FetchLibrariesForHotReloadResponseBuilder) updates,
+  ]) = _$FetchLibrariesForHotReloadResponse;
+}