docs/fluid-player-design.md records the approved target: single fixed-point actor authority, exact 10 Hz / 3-substep geometry, the three pacing policies with Action-paced default, explicit action durations, pending-effect and resumable-Inn ordering, lit-integer-LOS terrain-only observation memory, and the future v5 schema break. It also preserves the prior first-person acceptance failure and states plainly which parts are target rather than delivered behaviour. README points at the contract and documents the safe legacy-grid-final worktree checkout for operating on original run/replay files without conversion.