feat: Add auto update functionality (#4686)

packages/cli/src/utils/updateEventEmitter.ts

@@ -0,0 +1,13 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { EventEmitter } from 'events';
+
+/**
+ * A shared event emitter for application-wide communication
+ * between decoupled parts of the CLI.
+ */
+export const updateEventEmitter = new EventEmitter();