Make Homebrew tap updates resilient to concurrent releases

[roodboi]

Problem

Back-to-back releases can race in .github/workflows/release.yml: the tap checkout becomes stale before git push origin HEAD:main, causing a non-fast-forward rejection. This occurred in v4.0.2 run 33646729863 after the formula rendered and committed correctly. Rerunning the failed job from a fresh checkout succeeded.

Acceptance

• Homebrew publication retries from the latest hack-dance/homebrew-tap main after a non-fast-forward rejection.
• The formula is re-rendered after refreshing the tap checkout rather than force-pushing or overwriting unrelated tap changes.
• A deterministic test covers two release updates racing on the same formula.

Evidence

• Initial job: https://github.com/hack-dance/hack/actions/runs/33646729863/job/100303771890
• Successful retry: https://github.com/hack-dance/hack/actions/runs/33646729863/job/100304226524