While adding test coverage for mesh subdivision surface scenarios, a few
problems were noticed with vertex crease support.
This PR fixes:
- Used incorrect `crease_sharpnesses` instead of `corner_sharpnesses`
- Used incorrect value for an "infinitely sharp" vertex crease
- Unnecessarily wrote out Blender's `crease_vert` attribute as a primvar
Tests are added which validate everything we support.
Pull Request: https://projects.blender.org/blender/blender/pulls/126209
cb9ca2f7a7