feat: add LIMITED subscription status support with traffic-exhausted UX

- Add is_limited to Subscription type
- Show yellow traffic-exhausted badge on Subscription and AdminUsers pages
- SubscriptionCardExpired: amber theme with warning icon and buy-traffic CTA for limited
- Dashboard: route limited subscriptions to SubscriptionCardExpired
- Subscription page: show additional options (buy traffic) for limited subs
- Use is_limited boolean instead of status string comparison
- Add trafficLimited translations for ru, en, zh, fa
- AdminUserDetail StatusBadge: add limited yellow styling

src/pages/Dashboard.tsx

@@ -247,7 +247,9 @@ export default function Dashboard() {
             <div className="skeleton h-12 w-full rounded-xl" />
           </div>
         </div>
-      ) : subscription?.is_expired || subscription?.status === 'disabled' ? (
+      ) : subscription?.is_expired ||
+        subscription?.status === 'disabled' ||
+        subscription?.is_limited ? (
         <SubscriptionCardExpired
           subscription={subscription}
           balanceKopeks={balanceData?.balance_kopeks ?? 0}