Fix Stage 0 bootstrap and startup regression

Task 0.1: Create database parent directory before connecting
- main.py _lifespan now calls Path(database_path).parent.mkdir(parents=True,
  exist_ok=True) before aiosqlite.connect() so the app starts cleanly on
  a fresh Docker volume with a nested database path.

Task 0.2: SetupRedirectMiddleware redirects when db is None
- Guard now reads: if db is None or not is_setup_complete(db)
  A missing database (startup still in progress) is treated as setup not
  complete instead of silently allowing all API routes through.

Task 0.3: SetupGuard redirects to /setup on API failure
- .catch() handler now sets status to 'pending' instead of 'done'.
  A crashed backend cannot serve protected routes; conservative fallback
  is to redirect to /setup.

Task 0.4: SetupPage shows spinner while checking setup status
- Added 'checking' boolean state; full-screen Spinner is rendered until
  getSetupStatus() resolves, preventing form flash before redirect.
- Added console.warn in catch block; cleanup return added to useEffect.

Also: remove unused type: ignore[call-arg] from config.py.

Tests: 18 backend tests pass; 117 frontend tests pass.

frontend/src/components/__tests__/SetupGuard.test.tsx

@@ -0,0 +1,77 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { render, screen, waitFor } from "@testing-library/react";
+import { MemoryRouter, Routes, Route } from "react-router-dom";
+import { FluentProvider, webLightTheme } from "@fluentui/react-components";
+import { SetupGuard } from "../SetupGuard";
+
+// Mock the setup API module so tests never hit a real network.
+vi.mock("../../api/setup", () => ({
+  getSetupStatus: vi.fn(),
+}));
+
+import { getSetupStatus } from "../../api/setup";
+
+const mockedGetSetupStatus = vi.mocked(getSetupStatus);
+
+function renderGuard() {
+  return render(
+    <FluentProvider theme={webLightTheme}>
+      <MemoryRouter initialEntries={["/dashboard"]}>
+        <Routes>
+          <Route
+            path="/dashboard"
+            element={
+              <SetupGuard>
+                <div data-testid="protected-content">Protected</div>
+              </SetupGuard>
+            }
+          />
+          <Route
+            path="/setup"
+            element={<div data-testid="setup-page">Setup Page</div>}
+          />
+        </Routes>
+      </MemoryRouter>
+    </FluentProvider>,
+  );
+}
+
+describe("SetupGuard", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("shows a spinner while the setup status is loading", () => {
+    // getSetupStatus resolves eventually — spinner should show immediately.
+    mockedGetSetupStatus.mockReturnValue(new Promise(() => {}));
+    renderGuard();
+    expect(screen.getByRole("progressbar")).toBeInTheDocument();
+  });
+
+  it("renders children when setup is complete", async () => {
+    mockedGetSetupStatus.mockResolvedValue({ completed: true });
+    renderGuard();
+    await waitFor(() => {
+      expect(screen.getByTestId("protected-content")).toBeInTheDocument();
+    });
+  });
+
+  it("redirects to /setup when setup is not complete", async () => {
+    mockedGetSetupStatus.mockResolvedValue({ completed: false });
+    renderGuard();
+    await waitFor(() => {
+      expect(screen.getByTestId("setup-page")).toBeInTheDocument();
+    });
+    expect(screen.queryByTestId("protected-content")).not.toBeInTheDocument();
+  });
+
+  it("redirects to /setup when the API call fails", async () => {
+    // Task 0.3: a failed check must redirect to /setup, not allow through.
+    mockedGetSetupStatus.mockRejectedValue(new Error("Network error"));
+    renderGuard();
+    await waitFor(() => {
+      expect(screen.getByTestId("setup-page")).toBeInTheDocument();
+    });
+    expect(screen.queryByTestId("protected-content")).not.toBeInTheDocument();
+  });
+});