fix: 优化 kwReply 函数的错误处理逻辑，确保在获取关键词失败或结果为空时返回 nil

handler/kw/kw.go

@@ -128,12 +128,8 @@ func unRegKw(keyword string, groupId int64) {
 
 func kwReply(msg model.Message) (reply *model.Reply) {
 	w, err := kw.GetKW(msg.RawMsg, strconv.Itoa(int(msg.GroupInfo.GroupId)))
-	if err != nil {
-		return &model.Reply{
-			ReplyMsg:       "",
-			ReferOriginMsg: false,
-			FromMsg:        msg,
-		}
+	if err != nil || len(w) == 0 {
+		return nil
 	}
 	wlist := []string{}
 	for _, v := range w {