Move build files into pycode/memilio-simulation and update actions

[reneSchm]

Changes and Information

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

• Move pyproject.toml and CMakeLists.txt from project root (back) into pycode/memilio-simulation.
• Add MacOS build to PyPI release.
• Merge / move installation and download documentation to avoid repetition.
• Minor improvements.

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 and checked in the preview.
• 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 97.46%. Comparing base (1d8bbc2) to head (a98e473).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1566      +/-   ##
==========================================
- Coverage   97.47%   97.46%   -0.02%     
==========================================
  Files         190      190              
  Lines       15966    15966              
==========================================
- Hits        15563    15561       -2     
- Misses        403      405       +2     

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[reneSchm]

PyPI workflow without upload:

[reneSchm]

I merged all duplicate install and download sections (unless I overlooked one) into one for each C++, Python, and general setup / cloning. I also fixed a lot of spurious warnings while fixing my own mistakes, so maybe ask for an additional proof-reader for the docs.

[annawendler]

Thank you for these changes, this makes the installation more consistent and intuitive again! My comments are only regarding documentation.

[annawendler]

I found one last typo but otherwise this looks good :D

[reneSchm]

Thanks for your thorough review. I did not expect there to be that many doc changes, but I think this should make the installation easier to navigate.