fix(GRO-2358): wire signOut() at higher layer for no-access screen (#72)

UAT_PLAYBOOK.md

@@ -447,7 +447,8 @@ These cases cover the `CustomerPortal` initialisation path that bridges an Authe
 | TC-WEB-5.25.3 | Subsequent portal calls use the bridged session ID | After TC-WEB-5.25.1 succeeds, navigate to **Appointments**, **My Pets**, **Billing**, **Settings**. Inspect any `/api/portal/*` request in DevTools → Network. | Each portal API call carries an `X-Impersonation-Session-Id` header whose value equals the `sessionId` returned by `session-from-auth` (not a URL-param value). Each call returns 200 (or 404 for genuinely empty collections), never 401. |
 | TC-WEB-5.25.4 | No impersonation chrome for the customer's own session | After TC-WEB-5.25.1, scan the portal UI. | No amber border around the page. No "STAFF VIEW" watermark. No "End Impersonation" button in the sidebar. The customer is themselves; only impersonation sessions started via `?sessionId=` show the banner. |
 | TC-WEB-5.25.5 | 404 fallback for authenticated user with no client record | 1. Sign in via SSO with an Authentik account whose email is **not** present in `clients`. 2. Land on `/`. | `POST /api/portal/session-from-auth` returns 404. The portal renders a centred card titled **"Portal access not configured"** with the message about contacting the groomer and a **Sign out** button. No redirect loop, no portal chrome. |
-| TC-WEB-5.25.6 | 404 fallback Sign-out escape hatch | From TC-WEB-5.25.5 click **Sign out**. | `POST /api/auth/sign-out` fires; browser navigates to `/login`; the Authentik session cookie is cleared. Reloading `/` no longer hits 404 (will show the login page). |
+| TC-WEB-5.25.6 | 404 fallback Sign-out escape hatch (GRO-2358) | From TC-WEB-5.25.5 click **Sign out**. | The shared `signOut()` from `lib/auth-client` fires (same handler as `AdminLayout`); browser navigates to `/login`; the Authentik session cookie is cleared. Reloading `/` no longer hits 404 (will show the login page). The handler always navigates to `/login` — even if the network call to `/api/auth/sign-out` fails — so a transient auth-server hiccup never leaves the user trapped on an authenticated screen. |
+| TC-WEB-5.25.6b | 404 fallback Sign-out on deep-link (GRO-2358) | From TC-WEB-5.25.5, instead of staying on `/`, navigate directly to a portal sub-route (e.g. `/appointments`, `/pets`, `/billing`). The no-access card renders. Click **Sign out**. | The same shared `signOut()` handler fires and the browser navigates to `/login`. The no-access screen must surface an escape hatch on every authenticated route — not just `/` — so a stale or deep link into a portal the user has no access to can never trap them. |
 | TC-WEB-5.25.7 | Bridge precedence — impersonation URL wins | 1. Sign in via SSO as a customer. 2. Open a new tab to `https://uat.groombook.dev/?sessionId=<a-valid-staff-impersonation-session-id>`. | The impersonation path runs; the amber banner appears for the impersonated client. The Better Auth bridge is **not** called on this load (`session-from-auth` absent in Network). |
 | TC-WEB-5.25.8 | Bridge precedence — dev user wins | In dev mode (e.g. local) with `localStorage["dev-user"]` set to a client persona, navigate to `/`. | The dev-session path runs (`POST /api/portal/dev-session`). The Better Auth bridge is **not** called (`session-from-auth` absent in Network). Staff dev users still redirect to `/admin`. |
 | TC-WEB-5.25.9 | Staff Better Auth session does not run the customer bridge | Sign in via SSO with a staff identity. Navigate to `/`. | `App.tsx` routing redirects to `/admin`. `POST /api/portal/session-from-auth` is **not** called. |