iOS sprite-slide fix, faster Maya walk (3.1.1)

On iOS, switching between Maya's walk and her idle pose would drift her sprite a few pixels — looked like she was sliding to a stop instead of stopping. The frame swap and her position weren't landing on the same render tick, so the sprite caught up half a beat late. They commit together now, so the transition reads clean.

Maya's walk cycle was also a little under-stepped: she was moving across the scene faster than her legs were cycling, which made it look like she was gliding. Bumped the cycle speed so the legs match the actual movement.