Covers enqueue->claim->mark, atomic claim (no double dispatch, 8-thread race), retry fail->queued->failed, requeue_running_jobs, observability, worker max_concurrency. Popen fully mocked (no real agent spawned).
Covers enqueue->claim->mark, atomic claim (no double dispatch, 8-thread race), retry fail->queued->failed, requeue_running_jobs, observability, worker max_concurrency. Popen fully mocked (no real agent spawned).