After the test-suite prune, the Python slices (~2.3m each) are no longer
CI's critical path — Desktop E2E (5.2m, the longest job) and the Docker
build are, and both run on every python-lane PR even when the diff never
leaves tests/. Neither consumes the test suite: Playwright drives the
built app + hermes serve backend, and the image copies installed code.
New python_prod lane = python minus tests-only diffs. e2e-desktop and
docker gate on it; every pytest/lint lane keeps gating on python.
Fail-open contract preserved: .github/ changes and empty diffs set
python_prod=true, and runner infrastructure (scripts/run_tests.sh,
run_tests_parallel.py) is deliberately NOT tests-only since a bad
runner edit can mask real failures.
Replay over the last 231 main commits: 39 (17%) would skip both jobs,
cutting their critical path from ~8m to ~3m. E2E-verified through the
real script entrypoint (tests-only/prod/mixed/fail-open) + 83 tests/ci
green.
cc0af6b9e8