- Fix typo: mgail.com → gmail.com in flake.nix maintainer metadata
- Add -u (undefined vars) and -o pipefail to coverage.sh, consistent
with version-sync.sh and tag-release.sh
The idempotency guard only checked local tags, but CI checkouts
don't fetch tags. Add git ls-remote fallback so re-runs of the
Release workflow skip already-pushed tags.
Co-authored-by: jpoehnelt-bot <jpoehnelt-bot@users.noreply.github.com>
Justin Poehnelt