Motivation
Related to #241. Ideally we can configure ruff as pre-commit only and not install in the venv etc. in which case it doesn't need to use the hacky language: system approach (see #22). This would be the way to do it if we aren't using uv, or if we don't need ruff to be installed in the dev environment.

Summary of desired enhancement
Consider the best design approach here - I haven't really thought about it yet.