fix(webui): broadcast runtime model updates

Co-authored-by: Cursor <cursoragent@cursor.com>

webui/src/tests/app-layout.test.tsx

@@ -57,6 +57,7 @@ vi.mock("@/lib/nanobot-client", () => {
     defaultChatId: string | null = null;
     connect = connectSpy;
     onStatus = () => () => {};
+    onRuntimeModelUpdate = () => () => {};
     onError = () => () => {};
     onChat = () => () => {};
     sendMessage = vi.fn();

webui/src/tests/nanobot-client.test.ts

@@ -89,6 +89,26 @@ describe("NanobotClient", () => {
     });
   });
 
+  it("dispatches runtime model updates globally", () => {
+    const client = new NanobotClient({
+      url: "ws://test",
+      reconnect: false,
+      socketFactory: (url) => new FakeSocket(url) as unknown as WebSocket,
+    });
+    const handler = vi.fn();
+    client.onRuntimeModelUpdate(handler);
+    client.connect();
+    lastSocket().fakeOpen();
+
+    lastSocket().fakeMessage({
+      event: "runtime_model_updated",
+      model_name: "openai/gpt-4.1",
+      model_preset: "fast",
+    });
+
+    expect(handler).toHaveBeenCalledWith("openai/gpt-4.1", "fast");
+  });
+
   it("resolves newChat() via the server-assigned chat_id", async () => {
     const client = new NanobotClient({
       url: "ws://test",

webui/src/tests/thread-shell.test.tsx

@@ -12,6 +12,7 @@ function makeClient() {
     status: "open" as const,
     defaultChatId: null as string | null,
     onStatus: () => () => {},
+    onRuntimeModelUpdate: () => () => {},
     onChat: (chatId: string, handler: (ev: import("@/lib/types").InboundEvent) => void) => {
       let handlers = chatHandlers.get(chatId);
       if (!handlers) {

webui/src/tests/useNanobotStream.test.tsx

@@ -134,28 +134,6 @@ describe("useNanobotStream", () => {
     ]);
   });
 
-  it("reports runtime model name updates from message frames", () => {
-    const fake = fakeClient();
-    const onModelNameChange = vi.fn();
-    renderHook(
-      () => useNanobotStream("chat-model", EMPTY_MESSAGES, false, undefined, onModelNameChange),
-      {
-        wrapper: wrap(fake.client),
-      },
-    );
-
-    act(() => {
-      fake.emit("chat-model", {
-        event: "message",
-        chat_id: "chat-model",
-        text: "Switched model preset to `fast`.",
-        model_name: "openai/gpt-4.1",
-      });
-    });
-
-    expect(onModelNameChange).toHaveBeenCalledWith("openai/gpt-4.1");
-  });
-
   it("suppresses redundant stream confirmation after assistant media", () => {
     const fake = fakeClient();
     const { result } = renderHook(() => useNanobotStream("chat-img-result", EMPTY_MESSAGES), {