Refactor residue-name matching logic in selection.py

[ParthUppal523]

Fixes #5247

Changes made in this Pull Request:

• Introduced a helper function Selection._apply_match_by_resnames() to centralize residue-name matching logic.
• Refactored various classes to use the new helper method instead of implementing similar logic independently.
• Removed duplicated code related to residue-name matching from these selection classes.
• Verified that existing tests pass to ensure no change in behavior.

This refactor improves code maintainability by reducing duplication and providing a reusable utility for selections that operate on residue names.

LLM / AI generated code disclosure

LLMs or other AI-powered tools (beyond simple IDE use cases) were used in this contribution: no

PR Checklist

• Issue raised/referenced?
• Tests updated/added? (NA)
• Documentation updated/added?
• package/CHANGELOG file updated?
• Is your name in package/AUTHORS?
• LLM/AI disclosure was updated.

Developers Certificate of Origin

I certify that I can submit this code contribution as described in the Developer Certificate of Origin, under the MDAnalysis LICENSE.

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📚 Documentation preview 📚: https://mdanalysis--5294.org.readthedocs.build/en/5294/

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.82%. Comparing base (6e837a4) to head (baff88f).
⚠️ Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #5294      +/-   ##
===========================================
- Coverage    93.83%   93.82%   -0.01%     
===========================================
  Files          182      182              
  Lines        22501    22483      -18     
  Branches      3195     3195              
===========================================
- Hits         21114    21095      -19     
- Misses         924      925       +1     
  Partials       463      463              

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[BradyAJohnston]

On initial inspection this looks fine - but you need to update your branch from develop as this PR is currently attempting to delete some lines from AUTHORS and CHANGELOG

[ParthUppal523]

@BradyAJohnston , thank you for your feedback. I have updated the branch as you suggested.

[ParthUppal523]

Thank you @BradyAJohnston for approving the changes and merging the PR