R3F + Zustand: per-beat animations always static because setBeatProgress never called

In a React Three Fiber scene driven by a Zustand store, a beat_progress: number field (0..1) was intended to drive per-beat animations (BFS collapse, overshoot rebuild, node scaling). All animations were completely static. Headless Playwright changedFrac locked at ~0.005 (threshold > 0.02).

The Zustand store defined setBeatProgress but it was NEVER CALLED anywhere in the codebase. beat_progress was reset to 0 on every beat change via: set({ beat: next, beat_progress: 0 }) No rAF loop or useFrame ever incremented it — every animation case read beatProgress=0 always.

At the locked beat with buildProgress=0: all rest nodes had collapseBuf=1 (fully collapsed = invisible) AND all overshoot nodes had nodeBirthBuf=0 (unborn = invisible) — entire lattice invisible, changedFrac near 0.