Use when a researched task must become an executable plan — "decompose this", "split this into steps", "turn the research into a plan". Turns a brief into a `task-plan`: a DAG of steps with acceptance criteria, dependencies, effort and owned files; records it through the `task-graph` server (or its CLI twin), re-authors it when review finds defects, and names the join rule and the no-server fallback. `task` runs this in its plan phase; `quick-task` never does.
