* chore(docs): reduce warnings when generating docs
This is a bunch of small miscellaneous fixes that reduce the amount of
warnings logged when generating our new docs. The long term goal is to
get this list down to 0 warnings, but I'll do it in multiple PRs.
* satisfy doclint
This adds the new docs that are generated by API Extractor via TSDoc.
They are sparse because we do not yet use TSDoc in the codebase. This is
the starting point and from here we can work through all the different
classes and improve the documentation.
