- Add idle variation system: creatures randomly play Stand variations
(stretch, flap, look around) every 4-10s, then return to idle loop
- Deduplicate M2 instances at same position (was hidden before animation
made duplicates visible with different random start times)
- Adaptive M2 render distance: 350 units in open terrain, 180 in cities
- Restore terrain sampler-to-unit uniform bindings lost during texture
bind optimization (roads were invisible under grass)
- Safety: clamp bone count to 128, validate sequence indices, sanitize scale