docs: added component diagram
This is the source used for the docs under: https://wikitech.wikimedia.org/wiki/Portal:Toolforge/Admin/Build_Service
Bug: #325167
How to register an account on GitLab. To prevent spam, new accounts are locked until approved by an admin or the approver bot. You can also file an unlock request to expedite access.
Support: mw:GitLab, how to host a project on GitLab, #wikimedia-gitlab on libera.chat, #GitLab on Phabricator.
This is the source used for the docs under: https://wikitech.wikimedia.org/wiki/Portal:Toolforge/Admin/Build_Service
Bug: #325167