chore: replace TODO with doc comment for subcommand_lookup

[jdx]

Summary

• Removes outdated TODO comment about making subcommand_lookup non-public
• The field was already private (no pub keyword)
• Adds proper doc comment explaining the field's purpose as a cache for subcommand name lookups

🤖 Generated with Claude Code

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Note

Clarifies intent of the subcommand cache without changing behavior.

• Replaces TODO with a doc comment for subcommand_lookup (cache for subcommand name lookups including aliases) in lib/src/spec/cmd.rs
• No functional changes; serialization remains skipped for this field

^{Written by Cursor Bugbot for commit 59636b0. This will update automatically on new commits. Configure here.}

[Copilot]

Pull request overview

This PR removes an outdated TODO comment and replaces it with a proper documentation comment. The TODO indicated making the field non-public, but the field was already private (no pub keyword was present).

Changes:

• Replaced TODO comment with a doc comment explaining that subcommand_lookup is a cache for subcommand name lookups including aliases

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 46.66%. Comparing base (8c8ae53) to head (59636b0).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #434   +/-   ##
=======================================
  Coverage   46.66%   46.66%           
=======================================
  Files          46       46           
  Lines        6538     6538           
  Branches     6538     6538           
=======================================
  Hits         3051     3051           
  Misses       1730     1730           
  Partials     1757     1757           

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