fix: 移除本地token检查，由后端处理授权验证

- 移除 localStorage token 检查，避免与飞书免登并行执行
- 在飞书环境中始终尝试免登，由后端判断登录状态
- 解决'飞书应用配置错误'误导性提示

frontend/src/pages/login/index.tsx

@@ -21,22 +21,24 @@ export default function Login() {
   const [loading, setLoading] = useState(true)
   const [environment, setEnvironment] = useState<'feishu' | 'external' | null>(null)
   const [showQRCode, setShowQRCode] = useState(false)
+  const [shouldSkipAutoLogin, setShouldSkipAutoLogin] = useState(false) // 防止重复执行免登
 
   // 检查登录状态
   useEffect(() => {
-    const token = localStorage.getItem('token')
     const urlParams = new URLSearchParams(window.location.search)
     const redirect = urlParams.get('redirect')
+    const authCode = urlParams.get('auth_code')
 
-    if (token) {
-      if (redirect) {
-        window.location.href = redirect
-      } else {
-        navigate('/dashboard')
-      }
+    // 如果 URL 中有授权码，直接处理登录
+    if (authCode) {
+      const companyParam = urlParams.get('company')
+      handleFeishuLogin(authCode, companyParam || undefined)
       return
     }
 
+    // 不检查本地 token，让后端处理
+    // 继续执行环境检测和免登
+
     // 监听飞书登录成功事件
     const handleFeishuLoginSuccess = ((e: any) => {
       const { user, token } = e.detail