1110 Migrate Python packages to use pyproject.toml for builds

[HenrZu]

Changes and Information

Please briefly list the changes (main added features, changed items, or corrected bugs) made:

• replace setuptools setup.py with PEP 621 pyproject.toml across all Python subpackages
• add a reusable lint helper for packages that earlier used a custom pylint command
• update CI build/test actions

If need be, add additional information and what the reviewer should look out for in particular:

Merge Request - Guideline Checklist

Please check our git workflow. Use the draft feature if the Pull Request is not yet ready to review.

Checks by code author

• Every addressed issue is linked (use the "Closes #ISSUE" keyword below)
• New code adheres to coding guidelines
• No large data files have been added (files should in sum not exceed 100 KB, avoid PDFs, Word docs, etc.)
• Tests are added for new functionality and a local test run was successful (with and without OpenMP)
• Appropriate documentation within the code (Doxygen) for new functionality has been added in the code
• Appropriate external documentation (ReadTheDocs) for new functionality has been added to the online documentation
• Proper attention to licenses, especially no new third-party software with conflicting license has been added
• (For ABM development) Checked benchmark results and ran and posted a local test above from before and after development to ensure performance is monitored.

Checks by code reviewer(s)

• Corresponding issue(s) is/are linked and addressed
• Code is clean of development artifacts (no deactivated or commented code lines, no debugging printouts, etc.)
• Appropriate unit tests have been added, CI passes, code coverage and performance is acceptable (did not decrease)
• No large data files added in the whole history of commits(files should in sum not exceed 100 KB, avoid PDFs, Word docs, etc.)
• On merge, add 2-5 lines with the changes (main added features, changed items, or corrected bugs) to the merge-commit-message. This can be taken from the briefly-list-the-changes above (best case) or the separate commit messages (worst case).

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.30%. Comparing base (0a6b7e4) to head (e16e29d).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1409      +/-   ##
==========================================
+ Coverage   97.27%   97.30%   +0.02%     
==========================================
  Files         184      187       +3     
  Lines       15802    16024     +222     
==========================================
+ Hits        15372    15592     +220     
- Misses        430      432       +2     

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[reneSchm]

Thanks for putting in all that work!

The tomls look like they've got everything, I do have some questions on the CI and CMake, though.
Documentation also looks ok.

[HenrZu]

Moving the tests out of the installed package and switching the order of the install options (editable or not) is moved into #1440

[reneSchm]

Delaying merge to main, so that we can merge #1440 together with this PR.