Clean up version handling and python packaging

[ZLLentz]

This repo is using some systems that we've since moved away from:

• setup.py
• versioneer
• maybe others

We should reorganize to make it more like the other repositories we manage.

[rruiter87]

I recently made a pre-commit hook for TcUnit. You can take a look at that project how it is set up. I think it is a bit simpler than this one.

Also, I'm using ruff as a linter/formatter in the pre-commit for that repo. Ruff includes a lot of the standard python pre-commit tools that you want, and can automatically fix a lot of the issues it detects.

Might be a good source of inspiration.