Figure the best place for documentation to go in the existing docs

[romaricpascal]

What

Based on the list of alphagov/govuk-frontend#5224, decide where each piece of content would need to be added in our documentation.

Why

So we know where to add the new pieces of content to document the public API.

Who needs to work on this

Technical writer, Developers, Content designer?

Who needs to review this

Technical writer, Developers, Content designer?

Done when

• We've picked a place for new pieces of documentation to go in

[romaricpascal]

Done, we'll be adding a new 'Building your own JavaScript components' page to the Frontend docs.