feat(web): add ErrorBoundary, PageErrorBoundary, ComponentErrorBoundary

Implements GOO-63 audit requirement — React error boundaries with
Vietnamese-language fallback UI, Sentry capture, and "Thử lại" retry.

- ErrorBoundary: generic class component wrapping Sentry.captureException
- PageErrorBoundary: full-page fallback for route layouts
- ComponentErrorBoundary: inline widget fallback (compact + standard modes)
- Applied to ListingMap, CheckoutModal, SearchResults as first targets

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/web/components/subscription/checkout-modal.tsx

@@ -2,6 +2,7 @@
 
 import { AlertCircle, CreditCard, Loader2, Smartphone, Wallet } from 'lucide-react';
 import { useCallback, useState } from 'react';
+import { ComponentErrorBoundary } from '@/components/error-boundary';
 import { Badge } from '@/components/ui/badge';
 import { Button } from '@/components/ui/button';
 import {
@@ -78,7 +79,15 @@ const PLAN_TIER_LABELS: Record<string, string> = {
 // Component
 // ---------------------------------------------------------------------------
 
-export function CheckoutModal({
+export function CheckoutModal(props: CheckoutModalProps) {
+  return (
+    <ComponentErrorBoundary label="thanh toán">
+      <CheckoutModalInner {...props} />
+    </ComponentErrorBoundary>
+  );
+}
+
+function CheckoutModalInner({
   open,
   onOpenChange,
   plan,