fix: message can store Ex (#2371) (#2372)

(cherry picked from commit e6f1232582)

internal/api/msg.go

@@ -101,6 +101,7 @@ func (m MessageApi) newUserSendMsgReq(_ *gin.Context, params *apistruct.SendMsg)
 			SendTime:         params.SendTime,
 			Options:          options,
 			OfflinePushInfo:  params.OfflinePushInfo,
+			Ex:               params.Ex,
 		},
 	}
 	return &pbData

pkg/apistruct/manage.go

@@ -55,6 +55,9 @@ type SendMsg struct {
 
 	// OfflinePushInfo contains information for offline push notifications.
 	OfflinePushInfo *sdkws.OfflinePushInfo `json:"offlinePushInfo"`
+
+	// Ex stores extended fields
+	Ex string `json:"ex"`
 }
 
 // SendMsgReq extends SendMsg with the requirement of RecvID when SessionType indicates a one-on-one or notification chat.