Modernize packaging

[Zeitsperre]

Summary

This PR addresses several warnings and inconsistencies that are evident when examining the conda package and the testing output:

• The build backend was old, and some metadata fields were deprecated, slated for removal in 2027.
• The optional dependencies for some submodules were mixed in with the testing dependencies
• Some neccessary dependencies listed in the conda package were not listed in the package metadata.

This also addresses some issues in the GitHub workflows:

• Actions versions were quite out-of-date.
• The source_check job was installing black and isort but not running them.
• Dependencies installed in CI were not listed in the pyproject.toml.

Changes

• Updates several base packages to use newer versions
• The CLI entry point is now set, allowing for $ spotpy to work properly from the command line (click is now a core dependency).
• Drops Python3.9 code conventions
• Updates GitHub Actions to newer major versions
• GitHub Workflow adjustments
  • source_check is now lint: Linting libraries are now installed and run using --check
  • build_sdist is now test_build
• black and isort checks are now enforced, and the code base has been adapted to latest versions.
• The license and license-files metadata fields have been updated to be consistent with PEP 635.
• setup.py has been removed from the MANIFEST.in (deleted long ago).

Breaking Changes

The library now uses PEP 735 for installing testing and linting libraries. These groupings of dependencies are installed via:

$ python -m pip install --group lint,test,etc

The test recipe currently includes libraries to run optional components as well as libraries to run tests, so these still need to be split up a bit.

Relevant PEPs:

• https://peps.python.org/pep-0639/
• https://peps.python.org/pep-0735/

What's missing?

• The changelog is very out of date
• Many warnings are being raised from pytest (perhaps for another PR)

[coveralls]

Coverage Report for CI Build 26539512679

Coverage increased (+0.02%) to 66.791%

Details

• Coverage increased (+0.02%) from the base build.
• Patch coverage: 27 uncovered changes across 4 files (6 of 33 lines covered, 18.18%).
• 8 coverage regressions across 3 files.

Uncovered Changes

File	Changed	Covered	%
src/spotpy/analyser.py	20	1	5.0%
src/spotpy/algorithms/morris.py	6	0	0.0%
src/spotpy/algorithms/fast.py	1	0	0.0%
src/spotpy/algorithms/padds.py	1	0	0.0%
Total (8 files)	33	6	18.18%

Coverage Regressions

8 previously-covered lines in 3 files lost coverage.

File	Lines Losing Coverage	Coverage
src/spotpy/analyser.py	4	78.13%
src/spotpy/algorithms/morris.py	3	18.03%
src/spotpy/algorithms/fast.py	1	55.45%

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Coverage Stats

Relevant Lines:	5643
Covered Lines:	3769
Line Coverage:	66.79%
Coverage Strength:	2.0 hits per line

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💛 - Coveralls