Previously, this was a bare list of sub-pages, not in any discernible
order, and hard to parse.
Now the sub-pages are grouped in sections by topic. It's unlikely to be
the final word on how this material is arranged, but it's a clear
improvement on the existing arrangement and provides a good basis for
next steps.
Backport of dd0a116b93c40f9febf0e09614ad666af1191744 from main.
d9f37ac118