fix: 移除安装状态永久缓存，修复数据库重置后无法跳转安装页；优化登录401错误提示

frontend/src/router/index.ts

@@ -75,15 +75,12 @@ const router = createRouter({
   routes,
 })
 
-let installedChecked = false
 let isInstalled = false
 
 async function checkInstalled() {
-  if (installedChecked) return isInstalled
   try {
     const res: any = await systemApi.checkInstalled()
     isInstalled = res.installed
-    installedChecked = true
     return isInstalled
   } catch {
     return true

frontend/src/utils/request.ts

@@ -26,6 +26,10 @@ api.interceptors.response.use(
   (error) => {
     const message = error.response?.data?.error || error.message || 'Request failed'
     if (error.response?.status === 401) {
+      const isLoginRequest = error.config?.url?.includes('/auth/login')
+      if (isLoginRequest) {
+        ElMessage.error(message)
+      } else {
         const hadToken = !!localStorage.getItem('token')
         localStorage.removeItem('token')
         localStorage.removeItem('user')
@@ -35,6 +39,7 @@ api.interceptors.response.use(
         } else {
           ElMessage.error(message)
         }
+      }
     } else {
       ElMessage.error(message)
     }