Command: CombineSubLyrToPrnt
Description:
For each chosen parent layer, moves all objects that live on its child layers up into the parent layer (effectively flattens the hierarchy for those objects).
Required user inputs:
Usage example (one-liner):
Select parent layers and run CombineSubLyrToPrnt at Rhino’s prompt.
Notes:
This only moves object membership — child layers remain (but may become empty).
