Septop move files

[IAlibay]

Fixes #1918

Move SepTop unit and results files to separate files, along with minor QoL improvements.

Checklist

• All new code is appropriately documented (user-facing code must have complete docstrings).
• Added a news entry, or the changes are not user-facing.
• Ran pre-commit: you can run pre-commit locally or comment on this PR with pre-commit.ci autofix.

Manual Tests: these are slow so don't need to be run every commit, only before merging and when relevant changes are made (generally at reviewer-discretion).

• GPU integration tests
• example notebook testing
• packaging tests: run this for any large feature PRs or PRs that add test data.

Developers certificate of origin

• I certify that this contribution is covered by the MIT License here and the Developer Certificate of Origin at https://developercertificate.org/.

[IAlibay]

pre-commit.ci autofix

[codecov]

Codecov Report

❌ Patch coverage is 96.19289% with 15 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.35%. Comparing base (c60db06) to head (b435d8d).

Files with missing lines	Patch %	Lines
...protocols/openmm_septop/septop_protocol_results.py	90.62%	12 Missing ⚠️
src/openfe/protocols/openmm_septop/septop_units.py	98.85%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1932      +/-   ##
==========================================
- Coverage   94.62%   91.35%   -3.28%     
==========================================
  Files         206      208       +2     
  Lines       18285    18306      +21     
==========================================
- Hits        17303    16723     -580     
- Misses        982     1583     +601     

Flag	Coverage Δ
fast-tests	91.35% <96.19%> (?)
slow-tests	?

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[hannahbaumann]

Thanks @IAlibay , this looks good to me! I'm not sure if I saw all the QoL changes you made to the results or units files, so if there's anything particular you would like me to look at, please let me know.
This may make merging into the membrane PR a bit tricky, but that's also not a big problem.

[IAlibay]

This may make merging into the membrane PR a bit tricky, but that's also not a big problem.

That's a good point, let's aim to merge the membrane PR first. I can deal with the merge conflict here after the fact.

[github-actions]

No API break detected ✅