feat(display): render the style parameters from the display store

VisualSettings publishes the active style's parameter rows to the display
store, and the Display panel renders them with the shared row component;
a moved slider goes back through the store's setStyleParameter action.
The readout snaps a value to its step as the browser does, half-steps up
and an off-grid maximum down. A preset that resets the shown style's
uniforms republishes its rows, input for another style's parameters is
ignored, and a stopped owner takes its rows with it unless a newer owner
has published since. createStyleParameters is deprecated and builds its
rows the same way.

src/ui/shellElements.js

@@ -3,7 +3,6 @@ export function readShellElements(document = globalThis.document) {
   return {
     _rightPanelStack: document.getElementById('right-context-rail'),
     _sliderPanel: document.getElementById('param-slider-panel'),
-    _sliderContainer: document.getElementById('param-sliders'),
     _ppToggles: document.getElementById('pp-toggles'),
     _bloomBtn: document.getElementById('bloom-toggle'),
     _bloomSlider: document.getElementById('bloom-intensity-slider'),