Writing Plans

Use after discovery to write implementation plans with TDD-granularity steps. Produces plan.json (immutable definition, frozen after approval), progress.json (mutable execution state), and masterPlan.md (user-facing proposal for Orbit review). Every step is one component/feature; TDD rhythm (test, verify fail, implement, verify pass, commit) lives in its progress items. Consumes discovery.md from exploration phase. Make sure to use this skill whenever the user says discovery is done, exploration is finished, discovery.md is ready, or asks to write/create/draft the implementation plan — even if they don't mention plan.json or masterPlan.md by name. Also use when the user r…