Independent verification: supplier-admission premises of the #2265 substitution traced into PR2260 (0 FALSE / 0 MISSING-PROOF; no new kappa) - #2311

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/setup-python@v5. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/