chore: Skip homebrew updates for prereleases

[Copilot]

The update-homebrew job was triggering for all releases including alpha/beta/rc versions, causing homebrew formula updates for unstable builds.

Changes

• Added !github.event.release.prerelease check to update-homebrew job condition in .github/workflows/release.yml

The job now only runs for stable releases:

update-homebrew:
  needs: publish
  if: github.event_name == 'release' && !github.event.release.prerelease
  runs-on: ubuntu-latest

Original prompt

The homebrew update job should not create new relaeses for alpha prelreases

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