feat(antilopay): inject apay-tag meta on cabinet boot

Pairs with the bedolaga-bot commit that exposes
GET /cabinet/public/site-verification (JSON: { apay_tag: string | null }).

New useSiteVerification hook fires once on App mount, fetches the
configured tag value, and upserts <meta name='apay-tag' content='...'>
into document.head. When the bot returns null we proactively remove
any previously-rendered tag so toggling the env var off cleans up the
page.

Failure modes are silent — verification is best-effort and must
never block the cabinet from rendering. No admin UI field is needed:
the value lives in the bot's .env (ANTILOPAY_APAY_VERIFICATION_TAG),
matching how all other Antilopay credentials are configured.

src/App.tsx

@@ -32,6 +32,7 @@ import { ErrorBoundary } from './components/ErrorBoundary';
 import { PermissionRoute } from '@/components/auth/PermissionRoute';
 import { saveReturnUrl } from './utils/token';
 import { useAnalyticsCounters } from './hooks/useAnalyticsCounters';
+import { useSiteVerification } from './hooks/useSiteVerification';
 // Auth pages - load immediately (small)
 import Login from './pages/Login';
 import TelegramCallback from './pages/TelegramCallback';
@@ -229,6 +230,9 @@ function LegacySubscriptionRedirect() {
 
 function App() {
   useAnalyticsCounters();
+  // Pulls site-verification tokens (Antilopay apay-tag etc.) from the bot
+  // backend and injects matching <meta> tags into document.head.
+  useSiteVerification();
 
   return (
     <>