Stop cleaning corrupt cask dirs

[MikeMcQuaid]

• stop deleting corrupt cask directories from brew cleanup so missing metadata does not silently erase user state
• update brew doctor to recommend brew reinstall --cask --force <token> for those casks
• cover the new check_cask_corrupt_dirs guidance in Library/Homebrew/test/diagnostic_checks_spec.rb

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[Copilot]

Pull request overview

Stops brew cleanup from deleting “corrupt” Caskroom directories (missing metadata) and updates diagnostics to guide users toward force reinstalling affected casks instead.

Changes:

• Remove the automatic removal of corrupt Caskroom directories from brew cleanup.
• Update brew doctor’s check_cask_corrupt_dirs output to recommend brew reinstall --cask --force <token>.
• Add an RSpec example covering the new check_cask_corrupt_dirs guidance.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
Library/Homebrew/cleanup.rb	Removes the corrupt-cask-dir cleanup step so user state isn’t silently deleted.
Library/Homebrew/diagnostic.rb	Updates the doctor check message to list corrupt dirs and provide force-reinstall commands.
Library/Homebrew/test/diagnostic_checks_spec.rb	Adds test coverage for the updated doctor output.

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