Adds Python 3.13

[BradyPlanden]

Description

• Adds Python 3.13 w/ corresponding updates to CI
• Removes docs_utils in favour of local docstring definitions.

Fixes #4539

Type of change

Please add a line in the relevant section of CHANGELOG.md to document the change (include PR #)

Important checks:

Please confirm the following before marking the PR as ready for review:

• No style issues: nox -s pre-commit
• All tests pass: nox -s tests
• The documentation builds: nox -s doctests
• Code is commented for hard-to-understand areas
• Tests added that prove fix is effective or that feature works

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.67%. Comparing base (ed59259) to head (babcd8d).
⚠️ Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #5330      +/-   ##
===========================================
- Coverage    98.67%   98.67%   -0.01%     
===========================================
  Files          324      323       -1     
  Lines        28033    28020      -13     
===========================================
- Hits         27661    27648      -13     
  Misses         372      372              

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[agriyakhetarpal]

Thanks, @BradyPlanden! Nice cleanup, I remember implementing the documentation utilities over three years ago :) I restarted the Windows test where the worker crashed, otherwise it looks good to me. Could we try for Python 3.14 as well (in pybammsolvers first and then here)?

[BradyPlanden]

Thanks @agriyakhetarpal, it looks like we will have to wait for our dependencies to mature a bit more until we increment to Python 3.14. Here's the initial checklist when incrementing pybammsolvers to 3.14 and testing against this branch.

• Jax/Jaxlib needs to be incremented; however, this would require us to drop support for macOS-intel. A condition dependency will be required.
• Posthog 7.4.2 has breaking syntax with a finally block. Open fix: Avoid return from finally block to fix Python 3.14 SyntaxWarning PostHog/posthog-python#361
• Increment pybammsolvers

[agriyakhetarpal]

Thanks @BradyPlanden for doing the research on what's needed (and for opening the issue!). Let's go ahead with this.