Added fields not working with Unity editors drawn without IMGUI (ie 2022.3)

On recent Unity versions (tested with v2022.3.10f1 on my side), Unity is no longer drawing default inspector with IMGUI (but with Visual Elements). Making the added fields feature no longer working.

This can be verified by enabling "Use IMGUI Default Inspector" in the Project Settings > Editor.
When enabled added fields feature is working again.
When disabled, as Unity is no longer calling DrawDefaultInspector, the harmony patch is no longer effective, and RenderNewlyAddedFields is no longer called.

I guess an additional patch would be needed in NewFieldsRendererDefaultEditorPatch constructor to add compatibility with the new way Unity is drawing inspectors. Probably by adding a patch to CreateInspectorGUI, where you could add the creation of a new [IMGUIContainer](https://docs.unity3d.com/ScriptReference/UIElements.IMGUIContainer-ctor.html), which would call RenderNewlyAddedFields (onGUIHandler).

Start with the NewFieldsRendererDefaultEditorPatch constructor and trace how DrawDefaultInspector currently leads to RenderNewlyAddedFields. Reproduce the behavior in Unity 2022.3 with Use IMGUI Default Inspector enabled and disabled, then inspect CreateInspectorGUI and IMGUIContainer integration. Done means added fields render when Unity uses the Visual Elements inspector, while existing IMGUI behavior remains working.

Scritto dal modello di indicizzazione a partire dal testo della issue.