The e2e job already discovers tests/e2e/core/delivery/ (C12 messaging exactly-once, C13 cron virtual-clock soak) through `run_tests.sh --include-integration tests/e2e`; both need the 900 s per-file budget under load (C12 150-590 s on a loaded 20-core box). Cell 5 lives under tests/conformance/ and runs in the unit job.