Problem: pressing buttons without clicking on them (hotkeys, focus)

Aevyrie's thoughts:

• multiple ways to do a lot of things with UI
• thing I'm trying to do is an abstraction level above picking
• options: create an Interact event, mock picking events, another abstraction layer within picking?
• rough idea: keep existing types for Pointer<Click> etc, but generate them from a lower level tool. Move physical picking data into an Option.
• picking is generally in a pretty solid spot: capable and robust

PointerId:

• Alice: does not like Custom variant: Uuid is very complex without a lot of justification
• Alice: would like to pass in standardized information about mocked picking events (hotkey, focus etc)
• Aevyrie: exists to give a stable ID for the hovermap (entity isn't suitable for touches etc)
• Aevyrie: custom uses a Uuid because might be used for testing etc and avoid conflicts
• Aevyrie: needs to decouple stable ID vs type of input
• Aevyrie: duplicating pointers happens with viewports
• Aevyrie: ID must be stable for a given input device and context

Plan:

1. Refactor PointerId to split apart kind (Mouse, Touch, Virtual) and identifier, removing Custom variant.
2. Revise and merge physical mocking approach from https://github.com/bevyengine/bevy/pull/17399.
3. Long-term: think about moving pointer event abstractions up a level, or adding semantic UI actions.