Three containerTest cases covering the novel C1 piece — the rest of
the Phase C work has unit-test coverage already.
1. Writes CANCELED PG row with snapshot fields, completedAt set to
cancelledAt, error.raw set to cancelReason, runTags / taskIdentifier
/ payload preserved.
2. Emits runCancelled with full payload (id, friendlyId, status, error,
organization / project / environment ids).
3. Idempotent on double-pop: second call after the first returns the
existing row id (P2002 caught) and does not re-emit the event.
Real PG + Redis testcontainers. ~15s total.
Dan Sutton
f2ff1a97ac