User manual-test feedback after iteration-3 hip-stable + leg-rotation
fixes:
1. Animation too fast for actual map traversal → play walk_fwd_lower
and walk_upper with speed=0.5 (effective 1.6s cycle, was 0.8s).
2. Second half visually broken → was substrate's sign-flip trick where
leg.scl_y goes +1 (opposite of rest -1) and foot.pos.y flips
negative. Cascade foot.world.scl_y = +1 * -1 = -1 → foot rendered
Y-flipped. User: 'die füße ... darf hier die skalierung nicht negativ
werden'.
New cycle: each half extends ONE leg (scl_y=-1 matching rest) while
the other stays at scl_y=0 (collapsed/invisible). foot.world.scl_y
never goes negative — only [0, +1]. Alternating-leg gait. Substrate
first-half preserved verbatim; second-half mirrors with role swap.
bf5fe12e4c