fix(release): validate Homebrew cask in tap checkout

[meck93]

Summary

• tap the real Homebrew checkout before editing/auditing the generated cask
• use personal-tap audit instead of new-cask eligibility audit
• update the cask macOS dependency syntax for current Homebrew
• update release docs to match the tested flow

Local workflow simulation

• tapped meck93/tap locally
• copied Casks/capture-this.rb into the Homebrew tap checkout
• injected version 0.1.0-test.1 and the current release DMG SHA
• ran brew audit --cask meck93/tap/capture-this successfully
• installed with brew install --cask --verbose meck93/tap/capture-this successfully
• verified /Applications/CaptureThis.app has no com.apple.quarantine xattr

Verification

• ruby -e 'require "yaml"; YAML.load_file(".github/workflows/release.yml")'
• ruby -c Casks/capture-this.rb
• mise run lint
• mise run test
• mise run build