Fix index startup navigation test mock

The cold workspace URL navigation fix changed the / startup path for a matching persisted workspace. Index no longer renders a workspace Redirect there; it calls navigateToWorkspace so the centralized workspace navigation path owns the transition, then keeps the startup splash visible while that imperative navigation runs.

Update the test mock to expose navigateToWorkspace and assert that behavior directly. This keeps the test aligned with the route-shape fix and prevents CI failures on branches rebased over main.

packages/app/src/app/index.test.tsx

@@ -8,7 +8,7 @@ import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import type { HostRuntimeBootstrapState } from "./_layout";
 import type { ActiveWorkspaceSelection } from "@/stores/navigation-active-workspace-store";
 
-const { redirectMock, state } = vi.hoisted(() => {
+const { navigateToWorkspaceMock, redirectMock, state } = vi.hoisted(() => {
   const hoistedState = {
     pathname: "/",
     bootstrapState: {
@@ -22,6 +22,7 @@ const { redirectMock, state } = vi.hoisted(() => {
   };
 
   return {
+    navigateToWorkspaceMock: vi.fn(),
     redirectMock: vi.fn(),
     state: hoistedState,
   };
@@ -49,6 +50,7 @@ vi.mock("@/screens/startup-splash-screen", () => ({
 }));
 
 vi.mock("@/stores/navigation-active-workspace-store", () => ({
+  navigateToWorkspace: navigateToWorkspaceMock,
   useActiveWorkspaceSelection: () => state.workspaceSelection,
 }));
 
@@ -67,6 +69,7 @@ describe("Index route startup navigation", () => {
     };
     state.anyOnlineHostServerId = null;
     state.workspaceSelection = null;
+    navigateToWorkspaceMock.mockReset();
     redirectMock.mockReset();
 
     container = document.createElement("div");
@@ -101,7 +104,11 @@ describe("Index route startup navigation", () => {
 
     await renderIndex();
 
-    expect(redirectMock).toHaveBeenCalledWith("/h/server-1/workspace/workspace-a");
+    expect(navigateToWorkspaceMock).toHaveBeenCalledWith("server-1", "workspace-a", {
+      currentPathname: "/",
+    });
+    expect(redirectMock).not.toHaveBeenCalled();
+    expect(container.querySelector("[data-testid='startup-splash']")).not.toBeNull();
   });
 
   it("navigates to the host root when the persisted workspace targets a different server", async () => {