Highlight index 1 when filtering rooms

TODO.md

@@ -1,7 +1,5 @@
 # TODO
 
-- better initial highlight position when filtering
-
 - fix python getting stuck when loading large room
 - fix accounts in room list not getting their profile updated if mirage starts
   with a filter

src/gui/MainPane/RoomList.qml

@@ -46,13 +46,19 @@ HListView {
     }
 
     onFilterChanged: {
-        py.callCoro("set_substring_filter", ["all_rooms", filter])
+        py.callCoro("set_substring_filter", ["all_rooms", filter], () => {
+            if (filter) {
+                currentIndex = 1  // highlight the first matching room
+                return
+            }
 
             const item = model.get(currentIndex)
 
             if (
                 ! filter &&
-            item && ((
+                item && (
+                    currentIndex === 1 || // required, related to the if above
+                    (
                         currentShouldBeAccount &&
                         wantedUserId !== item.id
                     ) || (
@@ -60,9 +66,11 @@ HListView {
                             wantedUserId !== item.for_account ||
                             wantedRoomId !== item.id
                         )
-            ))
+                     )
+                )
             )
                 currentIndex = -1  // will trigger the correctTimer
+        })
     }