refactor(stores): unify data sources pattern and extract BaseManager base class

- Add BaseManager/CachedManager base classes to eliminate duplicate cache logic
- Add postListSources.ts with IPostListPagedSource interface
- Add groupListSources.ts with IGroupListPagedSource interface
- Refactor postManager to use CachedManager and Sources pattern
- Refactor groupManager to use CachedManager and Sources pattern
- Clean up duplicate methods in groupService.ts
- Fix TypeScript errors and remove mock data

src/services/groupService.ts

@@ -78,7 +78,13 @@ function normalizeAnnouncementCursor(
 // 群组服务类（纯 API 层）
 // SQLite/内存缓存编排由 groupManager 统一处理
 class GroupService {
-  async fetchGroupsFromApi(page = 1, pageSize = 20): Promise<GroupListResponse> {
+  // ==================== 群组管理 ====================
+
+  /**
+   * 获取群组列表
+   * GET /api/v1/groups
+   */
+  async getGroups(page = 1, pageSize = 20): Promise<GroupListResponse> {
     const response = await api.get<GroupListResponse>('/groups', {
       page,
       page_size: pageSize,
@@ -86,16 +92,20 @@ class GroupService {
     return normalizeGroupListResponse(response.data);
   }
 
-  async fetchGroupFromApi(id: string): Promise<GroupResponse> {
+  /**
+   * 获取群组详情
+   * GET /api/v1/groups/:id
+   */
+  async getGroup(id: string): Promise<GroupResponse> {
     const response = await api.get<GroupResponse>(`/groups/${encodeURIComponent(id)}`);
     return normalizeGroup(response.data);
   }
 
-  async fetchMembersFromApi(
-    groupId: string,
-    page = 1,
-    pageSize = 50
-  ): Promise<GroupMemberListResponse> {
+  /**
+   * 获取群组成员列表
+   * GET /api/v1/groups/:id/members
+   */
+  async getMembers(groupId: string, page = 1, pageSize = 50): Promise<GroupMemberListResponse> {
     const response = await api.get<GroupMemberListResponse>(
       `/groups/${encodeURIComponent(groupId)}/members`,
       {
@@ -106,8 +116,6 @@ class GroupService {
     return normalizeMemberListResponse(response.data);
   }
 
-  // ==================== 群组管理 ====================
-
   /**
    * 创建群组
    * POST /api/v1/groups
@@ -117,22 +125,6 @@ class GroupService {
     return normalizeGroup(response.data);
   }
 
-  /**
-   * 获取群组列表
-   * GET /api/v1/groups
-   */
-  async getGroups(page = 1, pageSize = 20): Promise<GroupListResponse> {
-    return this.fetchGroupsFromApi(page, pageSize);
-  }
-
-  /**
-   * 获取群组详情
-   * GET /api/v1/groups/:id
-   */
-  async getGroup(id: string): Promise<GroupResponse> {
-    return this.fetchGroupFromApi(id);
-  }
-
   /**
    * 获取当前用户在群组中的成员信息
    * GET /api/v1/groups/:id/me
@@ -211,14 +203,6 @@ class GroupService {
     await api.post(`/groups/${encodeURIComponent(groupId)}/leave`);
   }
 
-  /**
-   * 获取群组成员列表
-   * GET /api/v1/groups/:id/members
-   */
-  async getMembers(groupId: string, page = 1, pageSize = 50): Promise<GroupMemberListResponse> {
-    return this.fetchMembersFromApi(groupId, page, pageSize);
-  }
-
   /**
    * 移除群成员（踢人）
    * POST /api/v1/groups/:id/members/kick