checkout/setup-node/pnpm já estavam em v5/v6 (Node 24); o aviso restante
vinha de styfle/cancel-workflow-action@0.12.1 (node20) usado no fail-fast.
Documenta runtimes nativos em AGENT-OPS.md.
Co-authored-by: Francisco Solla <fsolla@users.noreply.github.com>
Add composite action wrapping styfle/cancel-workflow-action@0.12.1 and
invoke it with if: failure() on every parallel job in ci-pr.yml and ci.yml.
Workflow-level actions: write permission enables cancellation. Document
fail-fast behavior in docs/AGENT-OPS.md CI table.
Closes#52
Co-authored-by: Francisco Solla <fsolla@users.noreply.github.com>