feat: auto-close modals when success notification appears

- Add closeOthersSignal to success notification store
- Create useCloseOnSuccessNotification hook for modals to subscribe
- Update TopUpModal to auto-close on success events
- Update InsufficientBalancePrompt to auto-close on success events
- Update Subscription page to close all modals/forms on success events

This ensures that when a WebSocket event indicates successful payment
or subscription purchase, all related modals close automatically,
providing clear feedback to users.

src/components/InsufficientBalancePrompt.tsx

@@ -1,8 +1,9 @@
-import { useState } from 'react';
+import { useState, useCallback } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useQuery } from '@tanstack/react-query';
 import { balanceApi } from '../api/balance';
 import { useCurrency } from '../hooks/useCurrency';
+import { useCloseOnSuccessNotification } from '../store/successNotification';
 import TopUpModal from './TopUpModal';
 import type { PaymentMethod } from '../types';
 
@@ -28,6 +29,13 @@ export default function InsufficientBalancePrompt({
   const [showMethodSelect, setShowMethodSelect] = useState(false);
   const [selectedMethod, setSelectedMethod] = useState<PaymentMethod | null>(null);
 
+  // Auto-close modals when success notification appears
+  const handleCloseAll = useCallback(() => {
+    setShowMethodSelect(false);
+    setSelectedMethod(null);
+  }, []);
+  useCloseOnSuccessNotification(handleCloseAll);
+
   const { data: paymentMethods } = useQuery({
     queryKey: ['payment-methods'],
     queryFn: balanceApi.getPaymentMethods,