Publish API Docs using the Docusaurus TypeDoc API plugin

[audionerd]

This adds and configures TypeDoc for API Doc publishing using https://github.com/milesj/docusaurus-plugin-typedoc-api.

To run, make sure the xstate submodule is updated and built:

git co typedoc
git submodule init
git submodule update
cd xstate
yarn
cd ..
yarn
yarn docusaurus start

Package index is at /api/next XState is at /api/next/core

Unfinished:

• [ ] Actually fix the issue with the VersionBanner component which was preventing the docs from rendering (on this line). Disabled it via patch-package for now.
• [x] Use the name/label core instead of xstate for xstate core in URI (e.g.: /api/next/xstate)
• [x] Maybe just /api/<package> instead of /api/next/<package>?
• [ ] Switch from TSDoc syntax back to more familiar JSDoc (e.g.: @remarks)
• [ ] Fix missing links in @see?