Fix incorrect parameter names in docstrings

[eeshsaxena]

Fix incorrect parameter names in docstrings

Changes made in this Pull Request:

Several docstrings document parameter names that do not match their function signatures:

• MDAnalysis.lib.util.which documents programe (typo) instead of program.
• MemoryReader.add_transformations (coordinates/memory.py) documents transform_list instead of the actual *transformations parameter.
• MDAnalysis.guesser.base.GuesserBase.is_guessable documents guess instead of its attr_to_guess parameter (the sibling guess_attr already documents it correctly).

Documentation-only change; no behaviour is affected.

(Note: coordinates/base.py has the same add_transformations docstring issue, but it was left out of this PR because that file is not yet black-formatted and including it tripped the black CI on pre-existing, unrelated lines. Happy to do it in a separate PR if you would like.)

LLM / AI generated code disclosure

LLMs or other AI-powered tools (beyond simple IDE use cases) were used in this contribution: yes

Partial. An AI assistant was used to help identify the docstring/signature mismatches (via a script comparing documented parameters against function signatures) and to draft wording. Every change was manually reviewed and verified against the actual function signatures.

PR Checklist

• Tests? (n/a, documentation-only)
• Docs?
• CHANGELOG updated?
• Issue raised/referenced?
• LLM/AI disclosure updated.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.85%. Comparing base (32b7808) to head (63e1be4).

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #5412   +/-   ##
========================================
  Coverage    93.85%   93.85%           
========================================
  Files          182      182           
  Lines        22509    22509           
  Branches      3202     3202           
========================================
  Hits         21125    21125           
  Misses         922      922           
  Partials       462      462           

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[IAlibay]

Thanks for opening this PR @eeshsaxena - however, before we do any rerview, we ask you to fill in the AI declaration section that was in the original PR template.

[eeshsaxena]

Thanks @IAlibay, apologies for missing that - I've filled in the LLM/AI disclosure section now. I also trimmed the PR to leave out coordinates/base.py (its pre-existing non-black-formatted lines were tripping the black check); the remaining three files are black-clean.