feat: add platform audit export

apps/taro/src/pages/platform-admin/workbench/index.tsx

@@ -2,6 +2,7 @@ import { useEffect, useState } from 'react';
 import Taro from '@tarojs/taro';
 import { Button, Text, View } from '@tarojs/components';
 import {
+  exportPlatformAuditLogs,
   loadPlatformAuditLogs,
   loadPlatformInvoices,
   loadPlatformOverview,
@@ -21,6 +22,17 @@ function money(cents: unknown) {
   return `¥${(Number(cents || 0) / 100).toFixed(2)}`;
 }
 
+function downloadBase64File(filename: string, contentBase64: string, mimeType: string) {
+  if (typeof document === 'undefined') return false;
+  const link = document.createElement('a');
+  link.href = `data:${mimeType};base64,${contentBase64}`;
+  link.download = filename;
+  document.body.appendChild(link);
+  link.click();
+  link.remove();
+  return true;
+}
+
 export default function PlatformWorkbenchPage() {
   const [overview, setOverview] = useState<PlatformOverview | null>(null);
   const [tenants, setTenants] = useState<PlatformTenantItem[]>([]);
@@ -29,6 +41,7 @@ export default function PlatformWorkbenchPage() {
   const [banks, setBanks] = useState<PlatformQuestionBankItem[]>([]);
   const [grants, setGrants] = useState<PlatformQuestionBankGrant[]>([]);
   const [error, setError] = useState('');
+  const [busy, setBusy] = useState('');
 
   useEffect(() => {
     Promise.all([
@@ -54,6 +67,23 @@ export default function PlatformWorkbenchPage() {
     { name: '公共题库', path: '/pages/platform-admin/question-banks/index', meta: '地区题库、授权、披露范围' },
   ];
 
+  async function exportAuditLogs() {
+    setBusy('audit-export');
+    setError('');
+    try {
+      const payload = await exportPlatformAuditLogs({ format: 'csv', limit: 1000 });
+      const item = payload.item;
+      if (item?.contentBase64 && item.filename) {
+        const ok = downloadBase64File(item.filename, item.contentBase64, item.mimeType || 'text/csv');
+        Taro.showToast({ title: ok ? '已导出' : '已生成', icon: 'success' });
+      }
+    } catch (nextError) {
+      setError(nextError instanceof Error ? nextError.message : '审计导出失败');
+    } finally {
+      setBusy('');
+    }
+  }
+
   return (
     <View className='platform-page'>
       <View className='platform-shell'>
@@ -112,6 +142,9 @@ export default function PlatformWorkbenchPage() {
         </View>
         <View className='platform-section'>
           <Text className='platform-section-title'>最近平台审计</Text>
+          <View className='platform-actions'>
+            <Button className='platform-button' loading={busy === 'audit-export'} onClick={exportAuditLogs}>导出审计 CSV</Button>
+          </View>
           <View className='platform-list'>
             {auditLogs.map(item => (
               <View className='platform-row' key={item.id}>