fix(mini-user): 微信小程序补 Intl 兜底并去掉 toLocaleString

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/mini-user/src/pages/redeem-success/index.tsx

@@ -5,6 +5,7 @@ import PageShell from '../../components/PageShell';
 import SubPageHeader from '../../components/SubPageHeader';
 import { request, toast } from '../../lib/api';
 import { formatShanghaiDateTime } from '../../lib/datetime';
+import { formatMoney } from '../../lib/money';
 
 const LAST_REDEEM_RESULT_KEY = 'lastRedeemResult';
 
@@ -17,15 +18,6 @@ type RedeemRecord = {
   createdAt: string;
 };
 
-function formatMoney(amount: number) {
-  const n = Number(amount);
-  if (!Number.isFinite(n)) return '0.00';
-  const fixed = n.toFixed(2);
-  const [intPart, dec] = fixed.split('.');
-  const withComma = intPart.replace(/\B(?=(\d{3})+(?!\d))/g, ',');
-  return `${withComma}.${dec}`;
-}
-
 /** 与权益「历史记录」一致：2026-08-03 13:53:03（Asia/Shanghai） */
 function formatChinaDateTime(input?: string | null) {
   return formatShanghaiDateTime(input ?? new Date());