Removes publish_hotfix_release: a hotfix/* branch push published a GA release to Maven Central with no tag or review (QRun-IO/qbit-cdn#12, QRun-IO/qqq#1121). hotfix/* branches now run test_only; a hotfix release publishes from a reviewed vX.Y.Z tag through publish_release. Adds .github/workflows/release-rc.yml (reusable QRun-IO/.github qbit-release-rc): a manual dispatch, or merging a develop PR labelled release:rc, merges develop into the release line and the release/* push runs the existing CircleCI RC publish. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>