chore: import upstream snapshot with attribution

apps/sim/lib/copilot/chat-status.ts

@@ -0,0 +1,42 @@
+/**
+ * Chat Status Pub/Sub Adapter
+ *
+ * Broadcasts chat status events across processes using Redis Pub/Sub.
+ * Gracefully falls back to process-local EventEmitter when Redis is unavailable.
+ *
+ * The Redis channel and SSE label retain the legacy `task:status_changed`
+ * identifier so live status updates keep flowing across pods during a rolling
+ * deploy (old and new pods must publish/subscribe on the same channel).
+ */
+
+import { createPubSubChannel, type PubSubChannel } from '@/lib/events/pubsub'
+
+interface ChatStatusEvent {
+  workspaceId: string
+  chatId: string
+  type: 'started' | 'completed' | 'created' | 'deleted' | 'renamed'
+  streamId?: string
+}
+
+type ChatPubSubGlobal = typeof globalThis & {
+  _chatStatusChannel?: PubSubChannel<ChatStatusEvent> | null
+}
+
+const g = globalThis as ChatPubSubGlobal
+
+if (!('_chatStatusChannel' in g)) {
+  g._chatStatusChannel =
+    typeof window !== 'undefined'
+      ? null
+      : createPubSubChannel<ChatStatusEvent>({ channel: 'task:status_changed', label: 'task' })
+}
+
+const channel = g._chatStatusChannel
+
+export const chatPubSub = channel
+  ? {
+      publishStatusChanged: (event: ChatStatusEvent) => channel.publish(event),
+      onStatusChanged: (handler: (event: ChatStatusEvent) => void) => channel.subscribe(handler),
+      dispose: () => channel.dispose(),
+    }
+  : null