Safety: require 100% branch coverage - #3742

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4, actions/labeler@v5.0.0, Vankka/pr-target-branch-action@def32ec9d93514138d6ac0132ee62e120a72aed5. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/