feat: 前端对接 Profile/Messages/Settings 页面 API

- 3 消息页 + 2 资料编辑页 + 3 设置页 + 2 资料展示页
- api.ts 新增 Profile/Messages/ChangePassword 等类型和方法
- SSEContext 事件映射修复 + 断线重连修复
- 剩余页面加 USE_MOCK 双模式，52/55 页面已完成

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

frontend/lib/api.ts

@@ -136,9 +136,11 @@ export interface RefreshTokenResponse {
 }
 
 export interface UploadPolicyResponse {
-  access_key_id: string
+  q_sign_algorithm: string
+  q_ak: string
+  q_key_time: string
+  q_signature: string
   policy: string
-  signature: string
   host: string
   dir: string
   expire: number
@@ -153,6 +155,92 @@ export interface FileUploadedResponse {
   file_type: string
 }
 
+// ==================== 用户资料类型 ====================
+
+export interface BrandProfileInfo {
+  id: string
+  name: string
+  logo?: string
+  description?: string
+  contact_name?: string
+  contact_phone?: string
+  contact_email?: string
+}
+
+export interface AgencyProfileInfo {
+  id: string
+  name: string
+  logo?: string
+  description?: string
+  contact_name?: string
+  contact_phone?: string
+  contact_email?: string
+}
+
+export interface CreatorProfileInfo {
+  id: string
+  name: string
+  avatar?: string
+  bio?: string
+  douyin_account?: string
+  xiaohongshu_account?: string
+  bilibili_account?: string
+}
+
+export interface ProfileResponse {
+  id: string
+  email?: string
+  phone?: string
+  name: string
+  avatar?: string
+  role: string
+  is_verified: boolean
+  created_at?: string
+  brand?: BrandProfileInfo
+  agency?: AgencyProfileInfo
+  creator?: CreatorProfileInfo
+}
+
+export interface ProfileUpdateRequest {
+  name?: string
+  avatar?: string
+  phone?: string
+  description?: string
+  contact_name?: string
+  contact_phone?: string
+  contact_email?: string
+  bio?: string
+  douyin_account?: string
+  xiaohongshu_account?: string
+  bilibili_account?: string
+}
+
+export interface ChangePasswordRequest {
+  old_password: string
+  new_password: string
+}
+
+// ==================== 消息类型 ====================
+
+export interface MessageItem {
+  id: string
+  type: string
+  title: string
+  content: string
+  is_read: boolean
+  related_task_id?: string
+  related_project_id?: string
+  sender_name?: string
+  created_at?: string
+}
+
+export interface MessageListResponse {
+  items: MessageItem[]
+  total: number
+  page: number
+  page_size: number
+}
+
 // ==================== Token 管理 ====================
 
 function getAccessToken(): string | null {
@@ -338,7 +426,7 @@ class ApiClient {
   // ==================== 文件上传 ====================
 
   /**
-   * 获取 OSS 上传凭证
+   * 获取 COS 上传凭证
    */
   async getUploadPolicy(fileType: string = 'general'): Promise<UploadPolicyResponse> {
     const response = await this.client.post<UploadPolicyResponse>('/upload/policy', {
@@ -803,6 +891,64 @@ class ApiClient {
     return response.data
   }
 
+  // ==================== 用户资料 ====================
+
+  /**
+   * 获取当前用户资料
+   */
+  async getProfile(): Promise<ProfileResponse> {
+    const response = await this.client.get<ProfileResponse>('/profile')
+    return response.data
+  }
+
+  /**
+   * 更新用户资料
+   */
+  async updateProfile(data: ProfileUpdateRequest): Promise<ProfileResponse> {
+    const response = await this.client.put<ProfileResponse>('/profile', data)
+    return response.data
+  }
+
+  /**
+   * 修改密码
+   */
+  async changePassword(data: ChangePasswordRequest): Promise<{ message: string }> {
+    const response = await this.client.put<{ message: string }>('/profile/password', data)
+    return response.data
+  }
+
+  // ==================== 消息/通知 ====================
+
+  /**
+   * 获取消息列表
+   */
+  async getMessages(params?: { page?: number; page_size?: number; is_read?: boolean; type?: string }): Promise<MessageListResponse> {
+    const response = await this.client.get<MessageListResponse>('/messages', { params })
+    return response.data
+  }
+
+  /**
+   * 获取未读消息数
+   */
+  async getUnreadCount(): Promise<{ count: number }> {
+    const response = await this.client.get<{ count: number }>('/messages/unread-count')
+    return response.data
+  }
+
+  /**
+   * 标记单条消息已读
+   */
+  async markMessageAsRead(messageId: string): Promise<void> {
+    await this.client.put(`/messages/${messageId}/read`)
+  }
+
+  /**
+   * 标记所有消息已读
+   */
+  async markAllMessagesAsRead(): Promise<void> {
+    await this.client.put('/messages/read-all')
+  }
+
   // ==================== 健康检查 ====================
 
   /**