The fixed /tmp/bread-ecosystem-ci path races when multiple repos' dev/beta
workflows run close together on the same self-hosted runner — one job's
rm -rf/clone can stomp another's in-progress checkout, causing the
regenerate-index step to fail intermittently. Switch to mktemp -d.
Adds dev-release.yml (publishes on every push to dev) and beta-release.yml
(publishes on a beta-v* tag), mirroring the pattern landing in
bread-ecosystem/bread. Also creates the dev branch for this repo, which
didn't exist before — see bread-ecosystem/docs/release-channels.md for the
three-track policy.
GitHub Actions self-hosted runners need per-repo registration on a
personal account; Forgejo Actions' runner already serves every repo
with zero setup. Moves release publishing there (dl.breadway.dev stays
the primary bakery target; GitHub release upload is kept as the
fallback via an explicit token, since Forgejo Actions has no ambient
GITHUB_TOKEN) and adds a mirror workflow to keep GitHub in sync
automatically.
