feature: Do not collapse user defined header

Author: valkyrienyanko

Framework/Scenes/MenuUI/MetricsOverlay/MetricsOverlay.cs

@@ -156,7 +156,7 @@ private void RenderMetrics()
 
  private void RenderUserDefinedVariables()
  {
- if (_trackingVariables.Count == 0 || !ImGui.CollapsingHeader("User Defined"))
+ if (_trackingVariables.Count == 0 || !ImGui.CollapsingHeader("User Defined", ImGuiTreeNodeFlags.DefaultOpen))
  return;
 
  foreach (var kvp in _trackingVariables)