Don't need to assign random body parts to each tracker

[fire]

Describe the proposed feature and how it helps to overcome a problem or limitation

Use vive tracker support for null path, so you don't need to assign random body parts to each tracker

Other information about your context or usecase.

For use for full body tracking

If known, describe how your proposal will work, with code, pseudo-code, mock-ups, or diagrams

???

See XR_NULL_PATH support for HTCX_vive_tracker_interaction

Anything else

No response