switch to noarch?

### Comment:

It seems this library is headers only and byte identical across platforms.

Would you be open to switch the recipe to noarch: generic if possible?

I'm not entirely sure of all implications this would have but we could then potentially retire a duplicate from emscripten-forge for WASM.

Read the cgal-cpp-feedstock recipe and the comment thread to understand the proposed `noarch: generic` change and its implications. Confirm whether this headers-only package can use that setting across platforms; done means the recipe is valid with the change and the possible duplicate for WASM has been considered.

Written by the indexing model from the issue text.