Ansible role documentation rebuilt from the roles themselves

Role documentation across both automation repositories had drifted from what the roles do: some described the wrong operating system, some named an application without saying what the automation actually changed, and some was still in French.

Every role's page is now generated from the role itself, so the supported platforms, the variables and their defaults, and the list of steps all come from the code rather than from memory.

A check now enforces this, and it tests the content rather than the presence of headings - the earlier check passed on pages that were wrong in every one of the ways listed above.