Simplify natwidth generic logic.

Merge branch 'main' of git.argonaut-constellation.org:~alcinnz/CatTrap

Restrict exports for inline & paragraph styling libraries.

Seperate out Font API from internals.

Capture length of spans when lowering runs of inlines.

Strip out extraneous whitespace.

Actually query for desired font, remove needless Maybe.

Commit missing Inline implementation.