Code quality improvement

[lmmx]

Pre-commit is running a few standard checks, further improvement could be gained from:

• pylint
  • code
  • tests
    • remaining problems are ignorable
  • (not sure if this needs to be in CI tbh, just run when looking to edit)
• tryceratops
• TODO: investigate flake8/other options

[lmmx]

For example with flake8 see mcx: .github/workflows/lint.yml and Makefile

[lmmx]

I would also suggest adding an automated check for the maintenance of full docstring coverage (#13: now achieved).