Iterative Planner

Core Principle: Context Window = RAM. Filesystem = Disk. Write to disk immediately. The context window will rot. The files won't.

{plan-dir} = plans/plan_YYYY-MM-DD_XXXXXXXX/ (active plan directory under project root). Discovery: plans/.current_plan contains the plan directory name. One active plan at a time. Cross-plan context: plans/FINDINGS.md and plans/DECISIONS.md persist across plans (merged on close). plans/LESSONS.md persists across plans (updated on close, max 200 lines). plans/INDEX.md maps topics to plan directories (survives sliding window trim).

State Machine