feat(macos): add Canvas A2UI renderer

vendor/a2ui/renderers/lit/src/0.8/events/a2ui.ts

@@ -0,0 +1,28 @@
+/*
+ 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 { Action } from "../types/components.js";
+import { AnyComponentNode } from "../types/types.js";
+import { BaseEventDetail } from "./base.js";
+
+type Namespace = "a2ui";
+
+export interface A2UIAction extends BaseEventDetail<`${Namespace}.action`> {
+  readonly action: Action;
+  readonly dataContextPath: string;
+  readonly sourceComponentId: string;
+  readonly sourceComponent: AnyComponentNode | null;
+}

vendor/a2ui/renderers/lit/src/0.8/events/base.ts

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+/*
+ 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.
+ */
+
+export interface BaseEventDetail<EventType extends string> {
+  readonly eventType: EventType;
+}

vendor/a2ui/renderers/lit/src/0.8/events/events.ts

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+/*
+ 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 type * as A2UI from "./a2ui.js";
+import { BaseEventDetail } from "./base.js";
+
+const eventInit = {
+  bubbles: true,
+  cancelable: true,
+  composed: true,
+};
+
+type EnforceEventTypeMatch<T extends Record<string, BaseEventDetail<string>>> =
+  {
+    [K in keyof T]: T[K] extends BaseEventDetail<infer EventType>
+      ? EventType extends K
+        ? T[K]
+        : never
+      : never;
+  };
+
+export type StateEventDetailMap = EnforceEventTypeMatch<{
+  "a2ui.action": A2UI.A2UIAction;
+}>;
+
+export class StateEvent<
+  T extends keyof StateEventDetailMap
+> extends CustomEvent<StateEventDetailMap[T]> {
+  static eventName = "a2uiaction";
+
+  constructor(readonly payload: StateEventDetailMap[T]) {
+    super(StateEvent.eventName, { detail: payload, ...eventInit });
+  }
+}
+
+declare global {
+  interface HTMLElementEventMap {
+    a2uiaction: StateEvent<"a2ui.action">;
+  }
+}