feat: 为系统通知添加明确的操作结果摘要

为风险挑战确认和好友申请处理场景添加对应操作结果的中文摘要，替代原有的状态文本，让用户能更清晰地理解系统通知内容。

server/im_http.go

@@ -1494,8 +1494,12 @@ func serveIMRiskChallengeConfirm(wrt http.ResponseWriter, req *http.Request) {
 	if imReliableHTTPEventsEnabled(req) {
 		eventType := "security.risk." + decision
 		eventID := stableIMEventID("risk", challengeID, decision, challenge.State)
+		summary := "你已取消本次操作"
+		if decision == "continue" {
+			summary = "你已确认继续执行该操作"
+		}
 		if err = createIMSystemNotification(principal.TenantID, principal.Uid,
-			stableIMEventID(eventID, "notification"), eventType, "安全操作确认", decision,
+			stableIMEventID(eventID, "notification"), eventType, "安全操作确认", summary,
 			types.KVMap{"risk_challenge_id": challengeID}); err != nil {
 			writeIMError(wrt, req, http.StatusInternalServerError, 90000, imReasonInternal, "internal error", nil)
 			return
@@ -6410,11 +6414,13 @@ func serveIMFriendRequestAction(wrt http.ResponseWriter, req *http.Request) {
 	if imReliableHTTPEventsEnabled(req) {
 		eventType := "friend.request." + status
 		action := types.KVMap{}
+		summary := "对方已婉拒你的好友申请"
 		if status == types.FriendRequestAccepted {
 			action["topic"] = updated.ApplicantID.P2PName(updated.TargetID)
+			summary = "对方已同意你的好友申请"
 		}
 		if err = publishIMRelationEventWithAction(principal.TenantID, principal.Uid, updated.ApplicantID,
-			updated.RequestID+":"+status, eventType, "好友申请已处理", status, action); err != nil {
+			updated.RequestID+":"+status, eventType, "好友申请已处理", summary, action); err != nil {
 			writeIMError(wrt, req, http.StatusInternalServerError, 90000, imReasonInternal, "internal error", nil)
 			return
 		}