Unified Minions skill for both deterministic shell jobs and LLM subagent
orchestration. Replaces the older `gbrain-jobs` routing intent. Use when:
submitting gbrain jobs, shell/background tasks, spawning subagents,
checking progress, steering running work, pausing/resuming, parallel
fan-out. One durable, observable, steerable queue interface. Also carries
the durable-execution doctrine for any operation expected to exceed ~2
minutes: capability ladder, deadman checks that verify the result was
reported, and content-addressed stage checkpoints for expensive pipelines.
