5521a2f6c6
REWORK_PLAN: M4 → ✅ (slot-array + DRY core, 500 rounds clean). M6 undo
moved to TODO (feature work, not infra). M5 docker: nginx → Caddy
(simpler WS config). Milestone numbering clarified.
TODO: BUG-5 → FIXED. Added FEAT-M6 (transactional undo from plan),
BUG-10 (deact+reactivate double-act, distinct from BUG-5), BUG-11
(FE Combat.scenario pre-existing crash). Pipeline updated.