CI setup: pytest + coverage, linting, type checking, pre-commit

[simontaurus]

Set up GitHub Actions CI for oold-python: pytest + coverage reporting, linting, type checking, pre-commit hooks. Baseline current test coverage.

Acceptance Criteria

• GitHub Actions workflow running on push/PR
• pytest with coverage reporting
• Linting (ruff/flake8) and type checking (mypy) configured
• Pre-commit hooks set up
• Baseline coverage number documented
• migrate to uv
• Contribution guidelines with responsible AI usage

[raederan]

#89
gh-pages build for pre-releases fixed with setting for semantic versioning in enviromental tag rules on gh-pages branch like this:

• *alpha*
• *beta*
• *rc*

Is aligned to

oold-python/.github/workflows/on-release-main.yml

Lines 1 to 5 in 42edecd

	name: release-main
	on:
	push:
	tags: ['v[0-9]*']

Pages
https://oo-ld.github.io/oold-python/

#88 Success

[raederan]

• codecov configured on repo-level access: https://app.codecov.io/github/OO-LD/oold-python
• token added as secret repo-level oold-python (link above and login via GitHub and go to Settings to get the token): CODECOV_TOKEN -> https://github.com/OO-LD/oold-python/settings/secrets/actions

  oold-python/.github/workflows/main.yml

  Lines 54 to 58 in 42edecd

  	- name: Upload coverage reports to Codecov on Ubuntu / Python 3.11
  	uses: codecov/codecov-action@v4
  	if: ${{ matrix.platform == 'ubuntu-latest' && matrix.python-version == '3.11' }}
  	env:
  	CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}

• ORGA GitHub Apps settings -> allowed oold-python for codecov: https://github.com/OO-LD/oold-python/settings/installations

see also uv cookiecutter template docs for codecov setup
https://osprey-oss.github.io/cookiecutter-uv/features/codecov/

Baseline Coverage Number 64%, see codecov batch below or current state on first link above in this comment on codecov