kip-227: report candidate failures against the proposer's own prior block - #126

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: cla-assistant/github-action@v2.1.3-beta. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/