完善访客结束流程与转接可见性

- 会话结束后支持重新咨询，评价改为选星+快捷文案再提交
- 转接/分配事件写入操作人与目标坐席，工作台时间线与备注可见

server/internal/handler/session.go

@@ -594,11 +594,39 @@ func (h *SessionHandler) Assign(c *gin.Context) {
 		return
 	}
 
-	model.DB.Create(&model.SessionEvent{SessionID: session.ID, OperatorID: middleware.GetUserID(c), Action: "assign", Detail: "会话分配"})
+	operatorID := middleware.GetUserID(c)
+	operatorName := userDisplayName(operatorID)
+	targetName := userDisplayName(req.AgentID)
+	detail := "会话分配给 " + targetName
+	if operatorID == req.AgentID {
+		detail = operatorName + " 领取了会话"
+	} else {
+		detail = operatorName + " 将会话分配给 " + targetName
+	}
+	model.DB.Create(&model.SessionEvent{
+		SessionID:  session.ID,
+		OperatorID: operatorID,
+		Action:     "assign",
+		Detail:     detail,
+	})
 	session.AgentID = &req.AgentID
 	session.Status = "active"
 	broadcastSessionUpdate(session)
-	middleware.JSON(c, gin.H{"message": "分配成功"})
+	middleware.JSON(c, gin.H{"message": "分配成功", "detail": detail})
+}
+
+func userDisplayName(userID uint) string {
+	var user model.User
+	if err := model.DB.Select("id", "nickname", "username").First(&user, userID).Error; err != nil {
+		return "未知坐席"
+	}
+	if strings.TrimSpace(user.Nickname) != "" {
+		return user.Nickname
+	}
+	if strings.TrimSpace(user.Username) != "" {
+		return user.Username
+	}
+	return "未知坐席"
 }
 
 func (h *SessionHandler) Transfer(c *gin.Context) {
@@ -621,6 +649,19 @@ func (h *SessionHandler) Transfer(c *gin.Context) {
 		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "目标客服不存在或不可用"})
 		return
 	}
+	if session.AgentID != nil && *session.AgentID == req.AgentID {
+		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "不能转接给当前接待坐席"})
+		return
+	}
+
+	operatorID := middleware.GetUserID(c)
+	operatorName := userDisplayName(operatorID)
+	targetName := userDisplayName(req.AgentID)
+	fromName := ""
+	if session.AgentID != nil {
+		fromName = userDisplayName(*session.AgentID)
+	}
+
 	result := model.DB.Model(&model.Session{}).
 		Where("id = ? AND tenant_id = ? AND status = ?", session.ID, session.TenantID, "active").
 		Updates(map[string]interface{}{"agent_id": req.AgentID, "last_read_seq": 0})
@@ -633,16 +674,22 @@ func (h *SessionHandler) Transfer(c *gin.Context) {
 		return
 	}
 
+	// 详情写明「谁 → 谁」，便于接手坐席在备注/时间线中一眼看清
+	detail := operatorName + " 转接给 " + targetName
+	if fromName != "" && fromName != operatorName {
+		detail = operatorName + " 将会话由 " + fromName + " 转接给 " + targetName
+	}
+
 	model.DB.Create(&model.SessionEvent{
 		SessionID:  session.ID,
-		OperatorID: middleware.GetUserID(c),
+		OperatorID: operatorID,
 		Action:     "transfer",
-		Detail:     "会话转接",
+		Detail:     detail,
 	})
 	session.AgentID = &req.AgentID
 	broadcastSessionUpdate(session)
 
-	middleware.JSON(c, gin.H{"message": "转接成功"})
+	middleware.JSON(c, gin.H{"message": "转接成功", "detail": detail})
 }
 
 func (h *SessionHandler) End(c *gin.Context) {