feat(mix-visualizer): Phase 10 tuning — smooth waveform, bouncy collision, 8 knobs

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.

DeepDrftPublic.Client/Controls/MixWaveformVisualizer.razor.cs

@@ -202,28 +202,32 @@ public partial class MixWaveformVisualizer : ComponentBase, IAsyncDisposable
     // ── Bridge pushes. Each is a no-op until the module handle exists. ───────────────────────────
 
     /// <summary>
-    /// Push the seven control values to the module from the shared state. Used to seed on first render
-    /// and to re-push when the controls bar signals a change (lava reframe Wave R4). Each value is its
-    /// own dedicated dial now — no more R2 temp-remapping:
+    /// Push the eight control values to the module from the shared state. Used to seed on first render
+    /// and to re-push when the controls bar signals a change. Each value is its own dedicated dial:
     /// <list type="bullet">
-    ///   <item>scroll speed [0,1] is mapped to a visible time-span via <see cref="MixZoomMapping"/> and
-    ///         pushed through <c>setScrollSpeed</c> (higher speed → tighter window → faster scroll);</item>
-    ///   <item>gradient rotation speed → <c>setGradientRotationSpeed</c> (inert until Wave R3);</item>
-    ///   <item>gravity / heat / blob density / collision strength → their dedicated lava-physics dials;</item>
+    ///   <item>scroll speed [0,1] is mapped onto the useful zoom band via
+    ///         <see cref="MixZoomMapping.ScrollKnobToSeconds"/> and pushed through <c>setScrollSpeed</c>
+    ///         (higher speed → tighter window → faster scroll);</item>
+    ///   <item>gradient rotation speed → <c>setGradientRotationSpeed</c> (live OKLab anchor rotation);</item>
+    ///   <item>gravity / heat / collision strength → their dedicated lava-physics dials;</item>
+    ///   <item>fluid amount → <c>setFluidAmount</c> (blob count + volume); fluid viscosity →
+    ///         <c>setFluidViscosity</c> (cohesion / sphere-restoration) — the Phase 10 split of the
+    ///         former single density knob;</item>
     ///   <item>waveform width → the ribbon-extent uniform.</item>
     /// </list>
     /// </summary>
     private async Task PushControlsAsync()
     {
         if (_handle is null) return;
-        // Scroll speed is a normalized [0,1] axis; map it to the visible time-span the renderer scrolls
-        // through. The log map keeps the even-to-the-hand feel the old zoom slider had.
-        var visibleSeconds = MixZoomMapping.FractionToSeconds(ControlState.ScrollSpeed);
+        // Scroll speed is a normalized [0,1] axis; map it onto the useful zoom band (Phase 10 retune —
+        // the knob's full travel now covers the 60%–100% zoom range, dropping the dead slow/wide end).
+        var visibleSeconds = MixZoomMapping.ScrollKnobToSeconds(ControlState.ScrollSpeed);
         await _handle.InvokeVoidAsync("setScrollSpeed", visibleSeconds);
         await _handle.InvokeVoidAsync("setGradientRotationSpeed", ControlState.GradientRotationSpeed);
         await _handle.InvokeVoidAsync("setLavaGravity", ControlState.LavaGravity);
         await _handle.InvokeVoidAsync("setLavaHeat", ControlState.LavaHeat);
-        await _handle.InvokeVoidAsync("setBlobDensity", ControlState.BlobDensity);
+        await _handle.InvokeVoidAsync("setFluidAmount", ControlState.FluidAmount);
+        await _handle.InvokeVoidAsync("setFluidViscosity", ControlState.FluidViscosity);
         await _handle.InvokeVoidAsync("setCollisionStrength", ControlState.CollisionStrength);
         await _handle.InvokeVoidAsync("setWaveformWidth", ControlState.WaveformWidth);
     }