Revert "[eric] canvas: render ring gains the harness kill switch so A/B runs on identical bits"

This reverts commit 5c88246bd7.

frontend/src/app/pages/Dashboard/hooks/interaction/useRenderRing.ts

@@ -47,8 +47,7 @@ export function useRenderRing(
   rectRef.current = { x: cardX, y: cardY, w: cardWidth, h: cardHeight };
 
   useEffect(() => {
-    // Measurement escape hatch: lets the perf harness A/B ring-on vs ring-off on identical bits.
-    if (!active || localStorage.getItem('osw-render-ring') === 'off') return undefined;
+    if (!active) return undefined;
     let raf = 0;
     const evaluate = (): void => {
       raf = 0;