fix(GRO-2011): always fetch /api/setup/status, even for unauth users

The second useEffect in App skipped the setup/status fetch when
`!authDisabled && !session` was true. In the deployed bundle the
`needsSetup` state therefore stayed `null` for unauth users, and a
later render short-circuit rendered nothing — producing the blank
white viewport at https://uat.groombook.dev/login.

Drop the unauth skip clause so `/api/setup/status` is always fetched
as soon as the auth state is known. The unauth branch in the render
is handled before `needsSetup` is consulted, so this is safe and
removes the stuck-`null` state.

Adds:
- New unit test in src/__tests__/App.test.tsx asserting the
  unauthenticated path calls /api/setup/status.
- UAT playbook entry TC-WEB-5.1.5 covering the blank-viewport
  regression scenario.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

UAT_PLAYBOOK.md

@@ -53,6 +53,7 @@ export const { signIn, signOut, useSession, changePassword } = authClient;
 | TC-WEB-5.1.2 | OIDC redirect | Click OIDC login button | Redirected to OIDC provider, then back to app with session established |
 | TC-WEB-5.1.3 | Logout | Click logout button | Session cleared, redirected to login page |
 | TC-WEB-5.1.4 | Session indicator | After successful login | User info/initials visible in UI indicating active session |
+| TC-WEB-5.1.5 | Unauthenticated `/login` renders the form (GRO-2011) | In a private/incognito window with no session cookie, navigate to UAT `/login` | React root mounts; the GroomBook sign-in card with the OIDC button is visible. Network tab shows `/api/auth/get-session` 200, `/api/setup/status` 200, and the login form is rendered (NOT a blank white viewport). |
 
 ### 5.2 Authentication — VITE_API_URL Set