Run the current worktree as a production-shaped local dev instance with web, Slack, or both, on a real LLM + Postgres. Each developer uses their own set of Slack apps from their own machine's pool store, so many worktrees (yours and a teammate's) can run reachable at once without colliding. Use when asked to /dev-instance, "spin this up so I can QA it in Slack", or "let me test your branch end to end".