Rework the documentation on management commands.

Review Request #13001 — Created May 1, 2023 and submitted — Latest diff uploaded


Review Board


Our documentation on management commands was very limited, listing only
a few commands and in no specific order.

This change completely reworks the documentation to list all common
commands we display in rb-site manage --help. They go over basic
usage and options, show warnings for the more dangerous commands, and
provide links to useful reference docs.

Each set of commands are listed in a dedicated section, providing

There's a new rb-management-command directive and role, which will
make it easier to link to the necessary docs without using :ref:.

Two commands, find-large-diffs and invalidate-api-tokens, have been
added to the mange rb-site manage --help output.

Built the docs. Checked for build errors, spelling errors, and bad
links. Viewed them in the new docs UI.