feat: unify code-like components with shared CodeWindow, fix blog re-render loop, and stabilize layouts

apps/web/src/components/Marker.tsx

@@ -36,7 +36,7 @@ export const Marker: React.FC<MarkerProps> = ({
         style={{ backgroundColor: color }}
         aria-hidden="true"
       />
-      {children}
+      <span className="relative z-10 text-slate-900">{children}</span>
     </span>
   );
 };