[datlechin]

Why

• Release Build needs one switch between the self-hosted Mac and xcode-27, and that switch needs to keep working while the Mac is up.
• The nightly skip check could count a hosted run as Mac coverage.
• Signing, notarization and the feed stay on hosted runners, so nothing signed builds under the maintainer's account.

Change

• MAC_RUNNER replaces RELEASE_BUILD_RUNNER: unset is the Mac, github is xcode-27. The dispatch runner input overrides it.
• A weekly run on Sunday at 07:00 UTC always builds on xcode-27.
• The Changes job is gone: every nightly builds.
• release.yml, apple-signing, prepare-build and the release scripts match main.
• The ci rule says what can reach tablepro-release and when to read a fork PR before approving it. apple/RELEASING.md has the switch commands.

Verified

• actionlint, shellcheck, the Repo Hygiene tooling tests, the release tests on Python 3.9 and verify.sh agent-docs pass.