cask/audit: detect incorrect app case

[krehel]

Occasionally we get PR's or issues in homebrew/cask due to applications not matching the right case name on case-sensitive filesystems. These are relatively rare since most users run with the standard case-insensitive, but it's still a negative user experience.

This audit is intended to catch these cases.

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Opus 5 / Fable 5, validated manually and ran tests locally with brew lgtm --online

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[Copilot]

Pull request overview

Adds a new cask audit check to detect artifact path casing mismatches between a cask’s declared artifact paths and the extracted on-disk names, helping prevent breakage on case-sensitive filesystems.

Changes:

• Add a new audit_artifact_case audit that compares declared artifact path components to extracted path casing.
• Add RSpec coverage for matching case, mismatched case, missing artifacts, appdir binaries, and manual installers.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
Library/Homebrew/cask/audit.rb	Implements the new artifact_case audit by walking extracted artifacts and comparing on-disk casing to declared paths.
Library/Homebrew/test/cask/audit_spec.rb	Adds tests validating the new audit’s behavior across several artifact scenarios.

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[MikeMcQuaid]

Thanks!