feat(websocket): add global handler for subscription and balance notifications

- Extend WSMessage interface with balance, subscription, autopay, account, referral fields
- Create WebSocketNotifications component to handle all WS events
- Add component to Layout for global event listening
- Show toasts and invalidate queries on subscription/balance events
- Add translations for all notification types (ru, en, zh, fa)

src/components/layout/Layout.tsx

@@ -6,6 +6,7 @@ import { useAuthStore } from '../../store/auth';
 import LanguageSwitcher from '../LanguageSwitcher';
 import PromoDiscountBadge from '../PromoDiscountBadge';
 import TicketNotificationBell from '../TicketNotificationBell';
+import WebSocketNotifications from '../WebSocketNotifications';
 import AnimatedBackground from '../AnimatedBackground';
 import { contestsApi } from '../../api/contests';
 import { pollsApi } from '../../api/polls';
@@ -452,6 +453,9 @@ export default function Layout({ children }: LayoutProps) {
 
   return (
     <div className="flex min-h-screen flex-col">
+      {/* Global WebSocket notifications handler */}
+      <WebSocketNotifications />
+
       {/* Animated Background */}
       <AnimatedBackground />