kettle-dev 2.5.15: Reconcile historical GitHub releases

🏷️ release kettle-dev 🏷️ 2.5.15

Version 2.5.15 adds verified release-backfill checks, changelog reformatting, and update mode for existing GitHub Release notes. Maintainers gain explicit tools for reconciling historical metadata instead of treating every release operation as a new publication.

Read the upstream release notes for the complete changes and see the project repository for usage and installation.