feat(phase2c): 群聊与已读回执功能完整实现

Phase 2c 全部 14 个 Task 完成，包含：

后端（Go）：
- MinIO 文件存储服务集成（Docker + Go SDK + 通用上传 API）
- Group 模块完整实现（DAO + Service + Controller + Router + Wire）
  - 18 个群管理 REST API + 11 个 WS 群事件推送
  - 群创建/解散/邀请/踢人/退出/转让群主/设管理员/禁言/全体禁言/群公告/群昵称/免打扰/搜索
- IM Service 扩展（群消息发送/撤回 + @提醒 + 管理员无时限撤回）
- 已读回执后端（单聊会话级 last_read_msg_id + 群聊消息级 im_message_reads）
- 管理端群组管理（列表/详情/解散）
- 数据库迁移（3 张新表 + 2 张表字段扩展）

前端（uni-app）：
- 群聊 Store + API 封装 + 11 个 WS 事件监听
- 已读回执 UI（单聊已读/未读标记 + 群聊 X人已读 + 已读详情页）
- 7 个群聊页面（对话/创建/设置/成员/邀请/审批/搜索）
- 会话列表改造（全部/单聊/群聊 Tab + @标记 + 免打扰标识）

管理端（Vue 3 + Element Plus）：
- 群组列表页（搜索/分页/详情弹窗/解散群聊）
- 侧边栏群组管理入口

文档同步：进度/架构/设计/API/规范文档全部更新

Made-with: Cursor

backend/go-service/app/admin/controller/group_manage_controller.go

@@ -0,0 +1,94 @@
+// Package controller 提供 admin 模块的 HTTP 接口处理
+package controller
+
+import (
+	"strconv"
+
+	"github.com/echochat/backend/app/admin/service"
+	"github.com/echochat/backend/pkg/logs"
+	"github.com/echochat/backend/pkg/utils"
+	"github.com/gin-gonic/gin"
+	"go.uber.org/zap"
+)
+
+// GroupManageController 管理端群组管理控制器
+type GroupManageController struct {
+	groupManageService *service.GroupManageService
+}
+
+// NewGroupManageController 创建群组管理控制器实例
+func NewGroupManageController(svc *service.GroupManageService) *GroupManageController {
+	return &GroupManageController{groupManageService: svc}
+}
+
+// GetGroupList 获取群组列表
+// GET /api/v1/admin/groups?page=1&page_size=20&keyword=xxx
+func (ctl *GroupManageController) GetGroupList(c *gin.Context) {
+	funcName := "admin.group_manage_controller.GetGroupList"
+	ctx := c.Request.Context()
+
+	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
+	pageSize, _ := strconv.Atoi(c.DefaultQuery("page_size", "20"))
+	keyword := c.Query("keyword")
+
+	list, total, err := ctl.groupManageService.ListGroups(ctx, page, pageSize, keyword)
+	if err != nil {
+		logs.Error(ctx, funcName, "获取群组列表失败", zap.Error(err))
+		utils.ResponseError(c, "获取群组列表失败")
+		return
+	}
+
+	logs.Info(ctx, funcName, "获取群组列表成功",
+		zap.Int64("total", total), zap.Int("page", page))
+	utils.ResponseOK(c, gin.H{
+		"list":  list,
+		"total": total,
+	})
+}
+
+// GetGroupDetail 获取群组详情
+// GET /api/v1/admin/groups/:id
+func (ctl *GroupManageController) GetGroupDetail(c *gin.Context) {
+	funcName := "admin.group_manage_controller.GetGroupDetail"
+	ctx := c.Request.Context()
+
+	id, err := strconv.ParseInt(c.Param("id"), 10, 64)
+	if err != nil {
+		utils.ResponseBadRequest(c, "ID 格式错误")
+		return
+	}
+
+	detail, err := ctl.groupManageService.GetGroupDetail(ctx, id)
+	if err != nil {
+		logs.Error(ctx, funcName, "获取群组详情失败",
+			zap.Int64("group_id", id), zap.Error(err))
+		utils.ResponseError(c, "获取群组详情失败")
+		return
+	}
+
+	logs.Info(ctx, funcName, "获取群组详情成功", zap.Int64("group_id", id))
+	utils.ResponseOK(c, detail)
+}
+
+// DissolveGroup 解散群聊
+// DELETE /api/v1/admin/groups/:id
+func (ctl *GroupManageController) DissolveGroup(c *gin.Context) {
+	funcName := "admin.group_manage_controller.DissolveGroup"
+	ctx := c.Request.Context()
+
+	id, err := strconv.ParseInt(c.Param("id"), 10, 64)
+	if err != nil {
+		utils.ResponseBadRequest(c, "ID 格式错误")
+		return
+	}
+
+	if err := ctl.groupManageService.DissolveGroup(ctx, id); err != nil {
+		logs.Error(ctx, funcName, "解散群聊失败",
+			zap.Int64("group_id", id), zap.Error(err))
+		utils.ResponseError(c, "解散群聊失败")
+		return
+	}
+
+	logs.Info(ctx, funcName, "解散群聊成功", zap.Int64("group_id", id))
+	utils.ResponseOK(c, nil)
+}

backend/go-service/app/admin/provider.go

@@ -18,4 +18,6 @@ var AdminSet = wire.NewSet(
 	controller.NewOnlineController,
 	service.NewContactManageService,
 	controller.NewContactManageController,
+	service.NewGroupManageService,
+	controller.NewGroupManageController,
 )

backend/go-service/app/admin/router.go

@@ -15,6 +15,7 @@ func RegisterRoutes(
 	userCtrl *controller.UserManageController,
 	onlineCtrl *controller.OnlineController,
 	contactManageCtrl *controller.ContactManageController,
+	groupManageCtrl *controller.GroupManageController,
 	jwtAuth gin.HandlerFunc,
 ) {
 	// 管理端路由组：JWT 认证 + admin/super_admin 角色检查
@@ -38,5 +39,10 @@ func RegisterRoutes(
 		// 好友关系管理
 		adminGroup.GET("/contacts", contactManageCtrl.GetAllContacts)
 		adminGroup.DELETE("/contacts/:id", contactManageCtrl.DeleteContact)
+
+		// 群组管理
+		adminGroup.GET("/groups", groupManageCtrl.GetGroupList)
+		adminGroup.GET("/groups/:id", groupManageCtrl.GetGroupDetail)
+		adminGroup.DELETE("/groups/:id", groupManageCtrl.DissolveGroup)
 	}
 }

backend/go-service/app/admin/service/group_manage_service.go

@@ -0,0 +1,247 @@
+// Package service 提供 admin 模块的核心业务逻辑
+package service
+
+import (
+	"context"
+	"math"
+	"strconv"
+
+	groupDAO "github.com/echochat/backend/app/group/dao"
+	groupModel "github.com/echochat/backend/app/group/model"
+	"github.com/echochat/backend/pkg/logs"
+	"go.uber.org/zap"
+	"gorm.io/gorm"
+)
+
+// GroupManageService 管理端群组管理服务
+type GroupManageService struct {
+	db       *gorm.DB
+	groupDAO *groupDAO.GroupDAO
+}
+
+// NewGroupManageService 创建群组管理服务实例
+func NewGroupManageService(db *gorm.DB, groupDAO *groupDAO.GroupDAO) *GroupManageService {
+	return &GroupManageService{db: db, groupDAO: groupDAO}
+}
+
+// GroupListItem 管理端群组列表项
+type GroupListItem struct {
+	ID             int64  `json:"id"`
+	ConversationID int64  `json:"conversation_id"`
+	Name           string `json:"name"`
+	Avatar         string `json:"avatar"`
+	OwnerID        int64  `json:"owner_id"`
+	OwnerName      string `json:"owner_name"`
+	MemberCount    int64  `json:"member_count"`
+	MaxMembers     int    `json:"max_members"`
+	Status         int    `json:"status"`
+	IsAllMuted     bool   `json:"is_all_muted"`
+	CreatedAt      string `json:"created_at"`
+}
+
+// GroupDetailInfo 管理端群组详情
+type GroupDetailInfo struct {
+	GroupListItem
+	Notice     string            `json:"notice"`
+	IsSearchable bool            `json:"is_searchable"`
+	Members    []GroupMemberInfo `json:"members"`
+}
+
+// GroupMemberInfo 群成员信息
+type GroupMemberInfo struct {
+	UserID   int64  `json:"user_id"`
+	Username string `json:"username"`
+	Nickname string `json:"nickname"`
+	Role     int    `json:"role"`
+	IsMuted  bool   `json:"is_muted"`
+	JoinedAt string `json:"joined_at"`
+}
+
+// ListGroups 获取群组列表（分页 + 搜索）
+func (s *GroupManageService) ListGroups(ctx context.Context, page, pageSize int, keyword string) ([]GroupListItem, int64, error) {
+	funcName := "service.group_manage_service.ListGroups"
+	logs.Info(ctx, funcName, "获取群组列表",
+		zap.Int("page", page), zap.Int("page_size", pageSize), zap.String("keyword", keyword))
+
+	if page < 1 {
+		page = 1
+	}
+	if pageSize < 1 || pageSize > 100 {
+		pageSize = 20
+	}
+
+	offset := (page - 1) * pageSize
+
+	var groups []groupModel.Group
+	var total int64
+
+	query := s.db.WithContext(ctx).Model(&groupModel.Group{})
+	if keyword != "" {
+		query = query.Where("name ILIKE ?", "%"+keyword+"%")
+	}
+
+	if err := query.Count(&total).Error; err != nil {
+		return nil, 0, err
+	}
+
+	if err := query.Order("created_at DESC").Offset(offset).Limit(pageSize).Find(&groups).Error; err != nil {
+		return nil, 0, err
+	}
+
+	// 批量查询群主名称，避免 N+1
+	ownerIDs := make([]int64, 0, len(groups))
+	convIDs := make([]int64, 0, len(groups))
+	for _, g := range groups {
+		ownerIDs = append(ownerIDs, g.OwnerID)
+		convIDs = append(convIDs, g.ConversationID)
+	}
+	ownerNameMap := s.batchGetUsernames(ctx, ownerIDs)
+	memberCountMap := s.batchGetMemberCounts(ctx, convIDs)
+
+	list := make([]GroupListItem, 0, len(groups))
+	for _, g := range groups {
+		list = append(list, GroupListItem{
+			ID:             g.ID,
+			ConversationID: g.ConversationID,
+			Name:           g.Name,
+			Avatar:         g.Avatar,
+			OwnerID:        g.OwnerID,
+			OwnerName:      ownerNameMap[g.OwnerID],
+			MemberCount:    memberCountMap[g.ConversationID],
+			MaxMembers:     g.MaxMembers,
+			Status:         g.Status,
+			IsAllMuted:     g.IsAllMuted,
+			CreatedAt:      g.CreatedAt.Format("2006-01-02 15:04:05"),
+		})
+	}
+
+	totalPages := int(math.Ceil(float64(total) / float64(pageSize)))
+	logs.Info(ctx, funcName, "获取群组列表成功",
+		zap.Int64("total", total), zap.Int("total_pages", totalPages))
+
+	return list, total, nil
+}
+
+// GetGroupDetail 获取群组详情（含成员列表）
+func (s *GroupManageService) GetGroupDetail(ctx context.Context, groupID int64) (*GroupDetailInfo, error) {
+	funcName := "service.group_manage_service.GetGroupDetail"
+	logs.Info(ctx, funcName, "获取群组详情", zap.Int64("group_id", groupID))
+
+	group, err := s.groupDAO.GetByID(ctx, groupID)
+	if err != nil {
+		return nil, err
+	}
+
+	memberCount, _ := s.groupDAO.GetMemberCount(ctx, group.ConversationID)
+	ownerName := s.getUsername(ctx, group.OwnerID)
+
+	members, err := s.groupDAO.GetMembers(ctx, group.ConversationID)
+	if err != nil {
+		return nil, err
+	}
+
+	memberInfos := make([]GroupMemberInfo, 0, len(members))
+	for _, m := range members {
+		username := s.getUsername(ctx, m.UserID)
+		memberInfos = append(memberInfos, GroupMemberInfo{
+			UserID:   m.UserID,
+			Username: username,
+			Nickname: m.Nickname,
+			Role:     m.Role,
+			IsMuted:  m.IsMuted,
+			JoinedAt: m.JoinedAt.Format("2006-01-02 15:04:05"),
+		})
+	}
+
+	detail := &GroupDetailInfo{
+		GroupListItem: GroupListItem{
+			ID:             group.ID,
+			ConversationID: group.ConversationID,
+			Name:           group.Name,
+			Avatar:         group.Avatar,
+			OwnerID:        group.OwnerID,
+			OwnerName:      ownerName,
+			MemberCount:    memberCount,
+			MaxMembers:     group.MaxMembers,
+			Status:         group.Status,
+			IsAllMuted:     group.IsAllMuted,
+			CreatedAt:      group.CreatedAt.Format("2006-01-02 15:04:05"),
+		},
+		Notice:       group.Notice,
+		IsSearchable: group.IsSearchable,
+		Members:      memberInfos,
+	}
+
+	return detail, nil
+}
+
+// DissolveGroup 管理端解散群聊
+func (s *GroupManageService) DissolveGroup(ctx context.Context, groupID int64) error {
+	funcName := "service.group_manage_service.DissolveGroup"
+	logs.Info(ctx, funcName, "管理端解散群聊", zap.Int64("group_id", groupID))
+	return s.groupDAO.DissolveGroup(ctx, groupID)
+}
+
+// getUsername 通过用户 ID 获取用户名（优先昵称，其次用户名）
+func (s *GroupManageService) getUsername(ctx context.Context, userID int64) string {
+	var username string
+	s.db.WithContext(ctx).Table("auth_users").
+		Where("id = ?", userID).
+		Pluck("COALESCE(NULLIF(nickname, ''), username)", &username)
+	if username == "" {
+		return strconv.FormatInt(userID, 10)
+	}
+	return username
+}
+
+// batchGetUsernames 批量查询用户名，返回 userID → 显示名 映射
+func (s *GroupManageService) batchGetUsernames(ctx context.Context, userIDs []int64) map[int64]string {
+	result := make(map[int64]string, len(userIDs))
+	if len(userIDs) == 0 {
+		return result
+	}
+
+	type row struct {
+		ID       int64  `gorm:"column:id"`
+		Username string `gorm:"column:display_name"`
+	}
+	var rows []row
+	s.db.WithContext(ctx).Table("auth_users").
+		Select("id, COALESCE(NULLIF(nickname, ''), username) AS display_name").
+		Where("id IN ?", userIDs).
+		Find(&rows)
+
+	for _, r := range rows {
+		result[r.ID] = r.Username
+	}
+	for _, uid := range userIDs {
+		if _, ok := result[uid]; !ok {
+			result[uid] = strconv.FormatInt(uid, 10)
+		}
+	}
+	return result
+}
+
+// batchGetMemberCounts 批量查询会话的成员数，返回 conversationID → count 映射
+func (s *GroupManageService) batchGetMemberCounts(ctx context.Context, conversationIDs []int64) map[int64]int64 {
+	result := make(map[int64]int64, len(conversationIDs))
+	if len(conversationIDs) == 0 {
+		return result
+	}
+
+	type row struct {
+		ConversationID int64 `gorm:"column:conversation_id"`
+		Count          int64 `gorm:"column:cnt"`
+	}
+	var rows []row
+	s.db.WithContext(ctx).Table("im_conversation_members").
+		Select("conversation_id, COUNT(*) AS cnt").
+		Where("conversation_id IN ?", conversationIDs).
+		Group("conversation_id").
+		Find(&rows)
+
+	for _, r := range rows {
+		result[r.ConversationID] = r.Count
+	}
+	return result
+}