feat(lanes): show Add Lane auto-setup summary before closing modal

The three setup calls (profile/agents/mcp) fired after worktree
creation but their outcome was only logged to the console. Keep the
modal open with a ✓/✗ summary for a few seconds (or until dismissed)
so the user actually sees what happened, matching the original F5 design.

client/src/components/lanes/__tests__/AddLaneModal.test.tsx

@@ -158,7 +158,8 @@ describe("AddLaneModal", () => {
     expect(onAdded).toHaveBeenCalledWith(
       expect.objectContaining({ id: 9, status: "provisioning" })
     );
-    expect(onClose).toHaveBeenCalled();
+    // The setup summary stays on screen for a few seconds before auto-closing.
+    await waitFor(() => expect(onClose).toHaveBeenCalled(), { timeout: 4000 });
   });
 
   it("shows a server error and leaves the modal open instead of closing silently", async () => {
@@ -228,6 +229,31 @@ describe("AddLaneModal", () => {
     await user.click(screen.getByRole("button", { name: "Add lane" }));
 
     await waitFor(() => expect(onAdded).toHaveBeenCalled());
+    await waitFor(() => expect(onClose).toHaveBeenCalled(), { timeout: 4000 });
+  });
+
+  it("shows the setup summary and lets the user dismiss it early instead of waiting out the auto-close timer", async () => {
+    vi.mocked(api.lanes.branches).mockResolvedValue({ branches: ["main"], current: "main" });
+    vi.mocked(api.lanes.worktree).mockResolvedValue({
+      lane: { id: 44, title: "demo3", cwd: "/lanes/demo3", status: "provisioning" } as Lane,
+    });
+    const onClose = vi.fn();
+    renderModal({ onClose });
+    const user = userEvent.setup();
+
+    const repoField = screen.getByLabelText("Source repository");
+    await focusField(user, repoField);
+    await user.type(repoField, "/Users/tester/projects/repo");
+    await screen.findByLabelText("Branch to fork from");
+    await user.type(screen.getByLabelText("Title"), "demo3");
+    await user.click(screen.getByRole("button", { name: "Add lane" }));
+
+    expect(await screen.findByText("Setup")).toBeInTheDocument();
+    expect(onClose).not.toHaveBeenCalled();
+
+    const [dismissButton] = screen.getAllByRole("button", { name: "Cancel" });
+    if (!dismissButton) throw new Error("Cancel button not found");
+    await user.click(dismissButton);
     expect(onClose).toHaveBeenCalled();
   });
 });