Is there an existing issue for this?

• I have searched the existing issues and added correct labels.

Please describe the feature you have in mind and explain what the current shortcomings are?

The Gizmo Menu feature in Nuke addon settings is hard to use and very restrictive.
It only works if you have (All must be filled even if they don't necessarily depend on each other)

• toolbar name
• toolbar icon
• gizmo directory path
• gizmo definitions

Suggested implementation?

My suggestion enhance the UX of the setting and also modify the logic add_scripts_gizmo() for adding the gizmo menu.

This suggestion is inspired by Houdini Shelves Manager

Setting:

• Mode 1: Add a Gizmo Directory Path
  
• Mode 2: Add Gizmos By definitions
  

Describe alternatives you've considered:

No response