Live wall: pinned/docked cameras stop when their provider is switched off; admin-only empty-state CTA

- LiveView: localStorage pins carry image URLs, so they rendered (without
  credit) after an admin disabled the provider. Pins now show only while
  their provider is serving (server-26#198 licence gating).
- MapView: pinned/docked map players drop out once their provider leaves
  the serving list; credits are kept from the last answer so docked players
  keep attribution while the overlay is hidden.
- WallPanels: the "no camera provider enabled" link to /admin was a dead CTA
  for non-admins (bounced to /). Link shown to admins only, deep-linked to
  /admin#cameras; the admin page now honours a tab hash.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

drb-frontend/app/admin/page.tsx

@@ -1285,6 +1285,11 @@ export default function AdminPage() {
   const { user, isAdmin, loading: authLoading } = useAuth();
   const router = useRouter();
   const [tab, setTab] = useState<AdminTab>("features");
+  // Deep link to a tab (/admin#cameras), e.g. from the live wall's empty state.
+  useEffect(() => {
+    const h = window.location.hash.slice(1);
+    if (TAB_LABELS.some((t) => t.key === h)) setTab(h as AdminTab);
+  }, []);
 
   // Wait for the claims to resolve before deciding. isAdmin is false for the
   // first render of every cold load (typed URL, hard refresh, bookmark) while