Bug 1894945 - new Glean.js docs platform MVP

[rosahbruno]

This is a first pass of the new documentation platform. There is generated content in here about the major Glean.js features, but the documentation is not complete. There are other features/topics/things that will be documented.

Running the new docs

cd documentation
npm i
npm run dev

Pull Request checklist

• Quality: Make sure this PR builds and runs cleanly.
  • Inside the glean/ folder, run:
    • npm run test Runs all tests
    • npm run lint Runs all linters
• Tests: This PR includes thorough tests or an explanation of why it does not
• Changelog: This PR includes a changelog entry to CHANGELOG.md or an explanation of why it does not need one
• Documentation: This PR includes documentation changes, an explanation of why it does not need that or a follow-up bug has been filed to do that work
  • Documentation should be added to The Glean Book when making changes to Glean's user facing API
    • When changes to the Glean Book are necessary, link to the corresponding PR on the mozilla/glean repository
  • Documentation should be added to the Glean.js developer documentation when making internal code changes

[travis79]

Just a couple of nits, but this is looking good!

[chutten]

Thank you for your patience in waiting for me to take a gander. I like the structure and the implementation and can't wait to see how easy it'll be to edit and write new docs.

I do have (checks notes) 18 things to say about the PR, but I don't think there's a single one that should stop us from publishing it right away if you think it's best.

[rosahbruno]

@travis79 @chutten

Thank you both for the reviews! I made many changes based on the feedback you provided and you caught a lot of stuff that needed to be addressed now or in the future.

I created a [meta] bug for all this work and made child bugs for things that were brought up during this review and some things that still need to be documented.

https://bugzilla.mozilla.org/show_bug.cgi?id=1894943