Thank you very much for the feature request.
I added it to the list and will try to implement it in future versions.

For example:

Scene items:
  - Scene 1
  - Scene 2
   Menu Scenes:
    - Menu Scene 1
    - Menu Scene 2

Project Items:
  - Prefabs
  - Materials
  - Player.prefab
   Level Modules
    - Floor.fbx
    - Door.fbx
   Particles
    - rain.prefab
    - leaves.prefab