Improve member list highlighted item behavior

- When focusing the "Filter members" field, highlight the first item if
  none already is

- When pressing esc in the field, clear any highlight

TODO.md

@@ -1,5 +1,7 @@
 # TODO
 
+- event menu key right click
+- composer menu?
 - fix members not synced bug
 - fix local unread counters order
 - fix highlight when logging in to new account

src/gui/Pages/Chat/RoomPane/MemberView/MemberView.qml

@@ -84,10 +84,19 @@ HColumnLayout {
                     py.callCoro("set_substring_filter", [modelSyncId, text])
                 }
 
+                onFocusChanged: if (
+                    focus &&
+                    stackView.depth === 1 &&
+                    stackView.currentItem.currentIndex === -1
+                ) stackView.currentItem.currentIndex = 0
+
                 Keys.forwardTo: [stackView.currentItem]
                 Keys.priority: Keys.AfterItem
 
                 Keys.onEscapePressed: {
+                    if (stackView.depth === 1)
+                        stackView.currentItem.currentIndex = -1
+
                     roomPane.toggleFocus()
                     if (window.settings.clearMemberFilterOnEscape) text = ""
                 }