fix(webui): honor native host chrome

webui/src/App.tsx

@@ -79,6 +79,7 @@ import {
 } from "@/lib/api";
 import {
   createRuntimeHost,
+  isNativeRuntime,
   toRuntimeSurface,
 } from "@/lib/runtime";
 import { projectNameFromPath, scopeWithAccessMode } from "@/lib/workspace";
@@ -778,6 +779,14 @@ function formatPairingExpiry(seconds: number | null | undefined): string {
   return `${Math.ceil(seconds / 60)} min`;
 }
 
+function resolveRuntimeSurface(
+  surface: RuntimeSurface | null | undefined,
+  fallback: RuntimeSurface,
+): RuntimeSurface {
+  if (isNativeRuntime(surface)) return "native";
+  return surface ? toRuntimeSurface(surface) : fallback;
+}
+
 export default function App() {
   const { t } = useTranslation();
   const [state, setState] = useState<BootState>({ status: "loading" });
@@ -787,9 +796,7 @@ export default function App() {
     async (client: NanobotClient, fallbackSurface: RuntimeSurface) => {
       const boot = await fetchBootstrap("", bootstrapSecretRef.current);
       const url = deriveWsUrl(boot.ws_path, boot.token, boot.ws_url);
-      const runtimeSurface = boot.runtime_surface
+      const runtimeSurface = resolveRuntimeSurface(boot.runtime_surface, fallbackSurface);
-        ? toRuntimeSurface(boot.runtime_surface)
-        : fallbackSurface;
       const runtimeHost = createRuntimeHost(runtimeSurface, boot.runtime_capabilities);
       const tokenExpiresAt = boot.expires_in
         ? bootstrapTokenExpiresAt(boot.expires_in)
@@ -827,7 +834,7 @@ export default function App() {
           if (cancelled) return;
           if (secret) saveSecret(secret);
           const url = deriveWsUrl(boot.ws_path, boot.token, boot.ws_url);
-          const runtimeSurface = toRuntimeSurface(boot.runtime_surface);
+          const runtimeSurface = resolveRuntimeSurface(boot.runtime_surface, "browser");
           const runtimeHost = createRuntimeHost(runtimeSurface, boot.runtime_capabilities);
           const client = new NanobotClient({
             url,
@@ -1086,7 +1093,7 @@ function Shell({
   const temporarySessionsRef = useRef<Record<string, ChatSummary>>({});
   const effectiveRuntimeSurface =
     settingsSnapshot?.surface ?? settingsSnapshot?.runtime_surface ?? runtimeSurface;
-  const showHostChrome = effectiveRuntimeSurface === "native";
+  const showHostChrome = isNativeRuntime(effectiveRuntimeSurface);
   const showMainSidebar = view !== "settings";
   const activeTemporarySession = activeKey ? temporarySessions[activeKey] ?? null : null;
   const temporaryChatId = activeTemporarySession?.chatId ?? null;

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

@@ -310,6 +310,7 @@ describe("App layout", () => {
     sessionUpdateHandlers.clear();
     sidebarStateUpdateHandlers.clear();
     window.history.replaceState(null, "", "/");
+    Reflect.deleteProperty(window, "nanobotHost");
     setNavigatorPlatform("Linux x86_64");
     localStorage.removeItem("nanobot-webui.sidebar");
     localStorage.removeItem("nanobot-webui.sidebar.completed-runs.v1");
@@ -335,6 +336,7 @@ describe("App layout", () => {
 
   afterEach(() => {
     cleanup();
+    Reflect.deleteProperty(window, "nanobotHost");
     vi.useRealTimers();
     vi.unstubAllGlobals();
   });
@@ -1655,6 +1657,32 @@ describe("App layout", () => {
     await waitFor(() => expect(flowSidebar).toHaveStyle({ width: "272px" }));
   });
 
+  it("uses native chrome when the host bridge overrides browser gateway metadata", async () => {
+    Reflect.set(window, "nanobotHost", { pickFolder: vi.fn() });
+    vi.mocked(fetchBootstrap).mockResolvedValue({
+      token: "tok",
+      api_token: "api-tok",
+      ws_path: "/",
+      expires_in: 300,
+      runtime_surface: "browser",
+    });
+    mockFetchRoutes({
+      "/api/settings": {
+        ...baseSettingsPayload(),
+        surface: "browser",
+        runtime_surface: "browser",
+      },
+    });
+
+    render(<App />);
+
+    await waitFor(() => expect(connectSpy).toHaveBeenCalled());
+    await waitFor(() => {
+      expect(screen.getByTestId("sidebar-brand-mark")).toHaveClass("mt-5");
+    });
+    expect(document.documentElement).toHaveClass("native-host");
+  });
+
   it("switches to the next session when deleting the active chat", async () => {
     mockSessions = [
       {