LDrawLoader cleanup and docs improvement

[yomboprime]

Related PR: #23173

Description

This PR is just cleanup of some LDrawLoader small details I saw while creating the documentation.

Also added some improvements to the loader docs.

[gkjohnson]

Awesome! Great to have documentation for the loader. One note is that I am working on a relatively large PR for LDrawLoader to convert the logic to cache the geometry so I'd like to avoid conflicts if you're planning to make other changes. I'll try to retain the modifications you've made here in the upcoming PR, though.

[yomboprime]

Awesome! Great to have documentation for the loader. One note is that I am working on a relatively large PR for LDrawLoader to convert the logic to cache the geometry so I'd like to avoid conflicts if you're planning to make other changes. I'll try to retain the modifications you've made here in the upcoming PR, though.

I'm sorry for the conflicts. I'm not planning to do more PRs to the loader for now.

[mrdoob]

Thanks!