Require `zap` stanzas in new casks #24315

• New casks often omit zap, and the # No zap stanza required comment that marks a deliberate omission can't be audited, we've just used it for a fuzzy regex check to a apply a PR label. Add zap :not_required so a cask can declare it instead.


• Serialise it as an empty zap stanza so that older versions of Homebrew can still load these casks from the API.


• Audit new casks in official taps for a zap stanza on the OS and architecture being audited. CI audits each one, so this catches a cask that supports Linux but only has a zap in on_macos.


• Only suggest brew generate-zap when auditing macOS, as it only scans macOS paths, and have it warn that the app must have been launched before it prints zap :not_required.


• Fix Cask/UninstallMethodsOrder, which crashed on the non-hash argument of zap :not_required.

• [x] Have you followed our Contributing guidelines?


• [x] Have you checked for other open Pull Requests for the same change?


• [x] Have you explained what your changes do? Performance claims (e.g. "this is faster") must include brew benchmark results.


• [x] Have you explained why you'd like these changes included, not just what they do?


• [ ] For bug fixes, have you given step-by-step brew commands to reproduce the bug?


• [x] Have you written new tests (excluding integration tests)? Here's an example.


• [x] Have you successfully run brew lgtm (style, typechecking and tests) locally?

• [x] I did not use AI/LLM to create this PR, or I disclosed the tool/model below and reviewed its output; I did not attribute commits to AI and will answer maintainer questions and review comments myself without AI/LLM.

Claude with Opus 5.5 at Extra High effort, with local review and testing.