Ensure msgs are sent in right order, fix echo bug

bug: only one local echo message delegate could be seen because all
echo eventId were the same

src/qml/Chat/Timeline/EventList.qml

@@ -37,8 +37,11 @@ HRectangle {
         // Declaring this "alias" provides the on... signal
         property real yPos: visibleArea.yPosition
 
+        property int zz: 0
         onYPosChanged: {
             if (chatPage.category != "Invites" && yPos <= 0.1) {
+                zz += 1
+                print(zz)
                 //Backend.loadPastEvents(chatPage.roomId)
             }
         }

src/qml/EventHandlers/rooms.js

@@ -87,7 +87,7 @@ function onTimelineEventReceived(
         timelines.set(found[0], item)
     } else {
         // Multiple clients will emit duplicate events with the same eventId
-        timelines.upsert({"eventId": event_id},  item, true, 500)
+        timelines.upsert({"eventId": event_id}, item, true, 500)
     }
 }