fix: 添加 QR SDK 加载失败的降级方案

1. 优先尝试加载飞书官方 QR SDK
2. 如果 SDK 加载超时（5秒）或失败，自动降级到普通二维码
3. 添加详细的加载日志，方便调试

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/pages/login/QRCodeLogin.tsx

@@ -1,5 +1,6 @@
 import { useState, useEffect, useRef } from 'react'
 import { Dialog, Toast } from 'antd-mobile'
+import { QRCodeSVG } from 'qrcode.react'
 import { useNavigate } from 'react-router-dom'
 import styles from './QRCodeLogin.module.css'
 
@@ -11,7 +12,6 @@ declare global {
       goto: string
       width?: string
       height?: string
-      style?: string
     }) => {
       matchOrigin: (origin: string) => boolean
       matchData: (data: any) => boolean
@@ -25,26 +25,47 @@ interface QRCodeLoginProps {
 }
 
 // 动态加载飞书 QR SDK
-const loadFeishuQRSDK = (): Promise<void> => {
+const loadFeishuQRSDK = (): Promise<boolean> => {
-  return new Promise((resolve, reject) => {
+  return new Promise((resolve) => {
+    // 检查是否已经加载
     if (window.QR) {
-      resolve()
+      console.log('✅ Feishu QR SDK already loaded')
+      resolve(true)
       return
     }
 
-    // 检查是否已经加载过
+    console.log('📦 Loading Feishu QR SDK...')
-    const existingScript = document.getElementById('feishu-qr-sdk')
-    if (existingScript) {
-      existingScript.addEventListener('load', () => resolve())
-      existingScript.addEventListener('error', () => reject(new Error('Failed to load Feishu QR SDK')))
-      return
-    }
 
     const script = document.createElement('script')
     script.id = 'feishu-qr-sdk'
     script.src = 'https://lf-package-cn.feishucdn.com/obj/feishu-static/lark/passport/qrcode/LarkSSOSDKWebQRCode-1.0.3.js'
-    script.onload = () => resolve()
+    script.async = true
-    script.onerror = () => reject(new Error('Failed to load Feishu QR SDK'))
+    script.timeout = 5000 // 5秒超时
+
+    const timeoutId = setTimeout(() => {
+      console.warn('⚠️ Feishu QR SDK load timeout, using fallback')
+      resolve(false)
+    }, 5000)
+
+    script.onload = () => {
+      clearTimeout(timeoutId)
+      setTimeout(() => {
+        if (window.QR) {
+          console.log('✅ Feishu QR SDK loaded successfully')
+          resolve(true)
+        } else {
+          console.warn('⚠️ QR SDK loaded but window.QR not found, using fallback')
+          resolve(false)
+        }
+      }, 100)
+    }
+
+    script.onerror = () => {
+      clearTimeout(timeoutId)
+      console.warn('⚠️ Failed to load Feishu QR SDK, using fallback')
+      resolve(false) // 不 reject，而是返回 false 使用降级方案
+    }
+
     document.head.appendChild(script)
   })
 }
@@ -52,6 +73,8 @@ const loadFeishuQRSDK = (): Promise<void> => {
 export default function QRCodeLogin({ visible, onClose }: QRCodeLoginProps) {
   const navigate = useNavigate()
   const [status, setStatus] = useState<'loading' | 'pending' | 'scanning' | 'success'>('loading')
+  const [useFallback, setUseFallback] = useState(false)
+  const [qrcodeUrl, setQrcodeUrl] = useState('')
   const qrContainerRef = useRef<HTMLDivElement>(null)
   const qrObjRef = useRef<any>(null)
   const pollTimerRef = useRef<NodeJS.Timeout | null>(null)
@@ -70,18 +93,20 @@ export default function QRCodeLogin({ visible, onClose }: QRCodeLoginProps) {
       if (pollTimerRef.current) {
         clearTimeout(pollTimerRef.current)
       }
+      // 重置状态
+      setUseFallback(false)
+      setQrcodeUrl('')
     }
   }, [visible])
 
   const initQRCode = async () => {
     setStatus('loading')
-    try {
+    setUseFallback(false)
-      // 加载飞书 QR SDK
+    setQrcodeUrl('')
-      await loadFeishuQRSDK()
 
-      if (!window.QR) {
+    try {
-        throw new Error('QR SDK not loaded')
+      // 尝试加载飞书 QR SDK
-      }
+      const sdkLoaded = await loadFeishuQRSDK()
 
       // 生成登录会话
       const response = await fetch('/api/v1/auth/qrcode-login', {
@@ -98,12 +123,12 @@ export default function QRCodeLogin({ visible, onClose }: QRCodeLoginProps) {
         const authUrl = result.data.auth_url
         sessionIdRef.current = result.data.session_id
 
-        // 清空容器
+        if (sdkLoaded && window.QR) {
+          // 使用飞书官方 QR SDK
           if (qrContainerRef.current) {
             qrContainerRef.current.innerHTML = ''
           }
 
-        // 使用飞书官方 QR SDK 创建二维码
           qrObjRef.current = window.QR({
             id: 'feishu-qrcode-container',
             goto: authUrl,
@@ -112,8 +137,15 @@ export default function QRCodeLogin({ visible, onClose }: QRCodeLoginProps) {
           })
 
           setStatus('pending')
-        // 开始轮询登录状态
           startPolling(result.data.session_id)
+        } else {
+          // SDK 加载失败，使用普通二维码
+          console.log('📱 Using fallback QR code')
+          setQrcodeUrl(authUrl)
+          setUseFallback(true)
+          setStatus('pending')
+          startPolling(result.data.session_id)
+        }
       } else {
         Toast.show(result.message || '生成二维码失败')
       }
@@ -194,11 +226,43 @@ export default function QRCodeLogin({ visible, onClose }: QRCodeLoginProps) {
     }
   }
 
+  const handleRefresh = () => {
+    if (pollTimerRef.current) {
+      clearTimeout(pollTimerRef.current)
+    }
+    initQRCode()
+  }
+
   return (
     <Dialog
       visible={visible}
       content={
         <div className={styles.qrcodeContainer}>
+          {status === 'loading' && <div className={styles.loading}>正在生成二维码...</div>}
+
+          {useFallback && qrcodeUrl && (
+            <>
+              <div className={styles.qrcode}>
+                <QRCodeSVG
+                  value={qrcodeUrl}
+                  size={200}
+                  level="M"
+                  includeMargin={false}
+                />
+              </div>
+
+              <div className={styles.status} style={{ color: getStatusColor() }}>
+                {getStatusText()}
+              </div>
+
+              <p className={styles.tip} style={{ fontSize: '12px', color: '#999' }}>
+                💡 使用飞书扫码登录
+              </p>
+            </>
+          )}
+
+          {!useFallback && status !== 'loading' && (
+            <>
               <div id="feishu-qrcode-container" ref={qrContainerRef} className={styles.qrcode}></div>
 
               <div className={styles.status} style={{ color: getStatusColor() }}>
@@ -208,6 +272,8 @@ export default function QRCodeLogin({ visible, onClose }: QRCodeLoginProps) {
               <p className={styles.tip}>
                 💡 打开飞书 APP，扫一扫登录
               </p>
+            </>
+          )}
         </div>
       }
       onClose={onClose}