chore: initial import of standalone agentscope project

examples/agent/a2ui_agent/samples/client/lit/shell/events/events.ts

@@ -0,0 +1,35 @@
+/*
+ Copyright 2025 Google LLC
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+      https://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+import { HTMLTemplateResult } from "lit";
+
+const eventInit = {
+  bubbles: true,
+  cancelable: true,
+  composed: true,
+};
+
+export class SnackbarActionEvent extends Event {
+  static eventName = "snackbaraction";
+
+  constructor(
+    public readonly action: string,
+    public readonly value?: HTMLTemplateResult | string,
+    public readonly callback?: () => void
+  ) {
+    super(SnackbarActionEvent.eventName, { ...eventInit });
+  }
+}