SSS: sort rooms in lists by latest event arrival time

src/api/client_server/sync/msc4186.rs

@@ -406,6 +406,9 @@ pub(crate) async fn sync_events_v5_route(
 
     let mut all_rooms = all_joined_rooms;
     all_rooms.extend(invited_rooms_data(&sender_user));
+    all_rooms.sort_by_key(|r| {
+        services().rooms.timeline.last_timeline_count(&sender_user, &r.id).ok()
+    });
 
     let all_room_ids: Vec<_> = all_rooms.iter().map(|r| r.id.clone()).collect();
     let all_room_ids: Vec<_> = all_room_ids.iter().map(|id| &**id).collect();