Add tag handler for collecting crate items from rustdoc output (#12903)

This PR adds a tag handler for collecting crate items from rustdoc's
HTML output.

This will serve as the foundation for getting more insight into a
crate's contents.

Release Notes:

- N/A
8ccd2a0c99Marshall Bowers committed on 6/11/2024, 7:56:37 PM· committed by GitHubparent57b87be
8 files changedLine totals unavailable