Close out an entire epic in one session — every open child issue of a parent issue, worked by dispatched agents, reviewed and committed one at a time. Use when Josh points at a parent issue and wants the whole thing finished: 'close out the epic', 'let's do epic 40', 'knock out the children of #40', 'work through all of #40's sub-issues', 'finish the whole epic'. Also use when a ref he named — even plain 'let's work on #40' — turns out to have open sub-issues. Routing: if the ref has no open sub-issues it is a single issue, so hand off to the `issue` skill with that ref.