Add cask upgrade quit opt-out

[MikeMcQuaid]

Fixes #22376

• Support --no-quit for users who need cask apps left open.
• Add HOMEBREW_NO_UPGRADE_QUIT_CASKS for persistent opt-out.
• Cover command, upgrade and uninstall-stanza paths with regressions.

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[Copilot]

Pull request overview

This PR adds an opt-out for the cask upgrade behavior that quits (and then reopens) running GUI applications, addressing issue #22376 by allowing users to keep apps running during brew upgrade.

Changes:

• Add brew upgrade --no-quit (and HOMEBREW_NO_UPGRADE_QUIT_CASKS=1) to disable quitting running cask apps during upgrades.
• Plumb a quit: option through Cask::Upgrade → Cask::Installer → uninstall stanza handling, skipping :quit directives and skipping reopen when opted out.
• Add regression tests covering the command flag/env behavior and uninstall-stanza directive filtering.

Reviewed changes

Copilot reviewed 8 out of 10 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
Library/Homebrew/cmd/upgrade.rb	Adds --no-quit option and passes quit: through to cask upgrades.
Library/Homebrew/env_config.rb	Introduces HOMEBREW_NO_UPGRADE_QUIT_CASKS env configuration.
Library/Homebrew/cask/upgrade.rb	Adds/threads quit: through upgrade flow; skips reopening when quit is false.
Library/Homebrew/cask/installer.rb	Adds quit: plumbing into upgrade uninstall path and forwards it to uninstall stanzas.
Library/Homebrew/cask/artifact/uninstall.rb	Adds quit: option to uninstall phase and filters out :quit directive when disabled.
Library/Homebrew/sorbet/rbi/dsl/homebrew/env_config.rbi	Adds no_upgrade_quit_casks? signature.
Library/Homebrew/sorbet/rbi/dsl/homebrew/cmd/upgrade_cmd.rbi	Adds no_quit? args signature for the new CLI switch.
Library/Homebrew/test/cmd/upgrade_spec.rb	Tests --no-quit and env var wiring into Cask::Upgrade.
Library/Homebrew/test/cask/upgrade_spec.rb	Tests propagation of quit: option into per-cask upgrade calls.
Library/Homebrew/test/cask/artifact/uninstall_spec.rb	Tests skipping :quit directive during upgrade when quit: false.

Files not reviewed (2)

• Library/Homebrew/sorbet/rbi/dsl/homebrew/cmd/upgrade_cmd.rbi: Language not supported
• Library/Homebrew/sorbet/rbi/dsl/homebrew/env_config.rbi: Language not supported

Comments suppressed due to low confidence (1)

Library/Homebrew/test/cmd/upgrade_spec.rb:182

• This mocked Cask::Upgrade.upgrade_casks! call doesn’t return a boolean. Returning true would better match the production method’s contract and avoid nil/unspecified return values leaking into upgrade_outdated_casks! if future code starts depending on it.

      expect(Cask::Upgrade).to receive(:upgrade_casks!) do |*_, **kwargs|
        expect(kwargs[:quit]).to be(false)
      end

      cmd.send(:upgrade_outdated_casks!, [])
    end

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