Consider migrating to ruff instead of isort + black for code formatting/import sorting

[davenquinn]

In #88 we merged automatic formatting of code. This works great but has a few problems:

isort's import formatting works differently from IntelliJ/PyCharm's built in capabilities (which don't appear configurable). The main difference is around "known first party" code (e.g., macrostrat.***) which isort allows grouping separately.

This creates a bit of a back-and-forth exchange between IntelliJ and CI-based formatting in some changes.

Switching to a newer/all-in-one tool like ruff might help things, but only if there is an IntelliJ/PyCharm integration