_try_walk_step_assist compared goal surface Y to the capsule centre
(~0.9 m above floor) instead of the actual capsule bottom, disabling
the assist for any surface below ~0.925 m — every terrace we added.
The lift formula used offsets 0.45/0.55 instead of the full capsule
total half-height (CAPSULE_HALF_HEIGHT + PLAYER_CAPSULE_RADIUS = 0.9),
producing zero/negative lift.
Fix: guard uses actual_feet_y = pos.y - CAPSULE_HALF_HEIGHT - PLAYER_CAPSULE_RADIUS;
lift targets goal.y + total_half_height via clampf. Flat floor clicks
and cylinder bumps are unaffected (guard still disabled when goal.y is
at or below true feet level).
Expanded 45×45 district made the 18 m MaxHorizontalStep too restrictive
(floor diagonal ~63 m). Add HorizontalStepEnabled to MovementValidationOptions
(default false, matching DistrictBoundsEnabled pattern) so the check is
skipped unless explicitly opted in. Add test for disabled case (9 pass).
Update README and plan with the decision.
Planning doc for expanding the prototype client district to ~5×
current footprint with terraces, step geometry, and extra obstacles
for camera/nav stress QA.