CI / validate (pull_request) Failing after 5s
Runner probe on PR #35 (run 461, log job 1979): checkout@v4 succeeds (network fine) but the act container has node:20 + git 2.52 and NO python3 — 'python3 --version' exited 127, which was the failing check. Every validation step is python3-based, so make step 2 self-provisioning via apt when missing. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>