merge: 合并主分支改动并保留 ops 监控实现

合并 main 分支的最新改动到 ops 监控分支。
冲突解决策略：保留当前分支的 ops 相关改动，接受主分支的其他改动。

保留的 ops 改动：
- 运维监控配置和依赖注入
- 运维监控 API 处理器和中间件
- 运维监控服务层和数据访问层
- 运维监控前端界面和状态管理

接受的主分支改动：
- Linux DO OAuth 集成
- 账号过期功能
- IP 地址限制功能
- 用量统计优化
- 其他 bug 修复和功能改进

frontend/src/stores/app.ts

@@ -30,6 +30,7 @@ export const useAppStore = defineStore('app', () => {
   const contactInfo = ref<string>('')
   const apiBaseUrl = ref<string>('')
   const docUrl = ref<string>('')
+  const cachedPublicSettings = ref<PublicSettings | null>(null)
 
   // Version cache state
   const versionLoaded = ref<boolean>(false)
@@ -285,6 +286,9 @@ export const useAppStore = defineStore('app', () => {
   async function fetchPublicSettings(force = false): Promise<PublicSettings | null> {
     // Return cached data if available and not forcing refresh
     if (publicSettingsLoaded.value && !force) {
+      if (cachedPublicSettings.value) {
+        return { ...cachedPublicSettings.value }
+      }
       return {
         registration_enabled: false,
         email_verify_enabled: false,
@@ -296,6 +300,7 @@ export const useAppStore = defineStore('app', () => {
         api_base_url: apiBaseUrl.value,
         contact_info: contactInfo.value,
         doc_url: docUrl.value,
+        linuxdo_oauth_enabled: false,
         version: siteVersion.value
       }
     }
@@ -308,6 +313,7 @@ export const useAppStore = defineStore('app', () => {
     publicSettingsLoading.value = true
     try {
       const data = await fetchPublicSettingsAPI()
+      cachedPublicSettings.value = data
       siteName.value = data.site_name || 'Sub2API'
       siteLogo.value = data.site_logo || ''
       siteVersion.value = data.version || ''
@@ -329,6 +335,7 @@ export const useAppStore = defineStore('app', () => {
    */
   function clearPublicSettingsCache(): void {
     publicSettingsLoaded.value = false
+    cachedPublicSettings.value = null
   }
 
   // ==================== Return Store API ====================

frontend/src/stores/auth.ts

@@ -159,6 +159,27 @@ export const useAuthStore = defineStore('auth', () => {
     }
   }
 
+  /**
+   * 直接设置 token（用于 OAuth/SSO 回调），并加载当前用户信息。
+   * @param newToken - 后端签发的 JWT access token
+   */
+  async function setToken(newToken: string): Promise<User> {
+    // Clear any previous state first (avoid mixing sessions)
+    clearAuth()
+
+    token.value = newToken
+    localStorage.setItem(AUTH_TOKEN_KEY, newToken)
+
+    try {
+      const userData = await refreshUser()
+      startAutoRefresh()
+      return userData
+    } catch (error) {
+      clearAuth()
+      throw error
+    }
+  }
+
   /**
    * User logout
    * Clears all authentication state and persisted data
@@ -233,6 +254,7 @@ export const useAuthStore = defineStore('auth', () => {
     // Actions
     login,
     register,
+    setToken,
     logout,
     checkAuth,
     refreshUser