Smooth the loudness contour (~50 ms envelope at preprocessing + decode-time, plus
smootherstep render reconstruction); retune wax↔waveform collision to bouncy/sub-unity
(no explosion/stuck/jitter); split the bubbles knob into fluid-amount + fluid-viscosity
(cohesion via uniform-only smin/wobble); retune scroll/gravity/heat/width ranges; make
the colour rotation visible and boost OKLab chroma; the controls bar now holds its
layout and hides only its knobs via a Visible parameter.