Remove requestAnimationFrame hack and use proper ESLint disable

Replaced the requestAnimationFrame workaround with an explicit ESLint
disable comment. The setState call in this effect is intentional and
valid - it's syncing component state with localStorage when switching
to the custom theme, which is a legitimate use case for effects.

This is clearer and more maintainable than hiding the intent with
requestAnimationFrame.

Signed-off-by: Charles de Dreuille <charles.dedreuille@gmail.com>

docs-ui/src/components/CustomTheme/customTheme.tsx

@@ -73,10 +73,10 @@ export const CustomTheme = () => {
         storedTheme = defaultTheme;
         localStorage.setItem('customThemeCss', storedTheme);
       }
-      // Defer setState to avoid synchronous call in effect
-      requestAnimationFrame(() => {
-        setCustomTheme(storedTheme!);
-      });
+      // This setState is intentional - we're syncing component state with localStorage
+      // when the user switches to the custom theme. This is a valid effect pattern.
+      // eslint-disable-next-line react-hooks/set-state-in-effect
+      setCustomTheme(storedTheme);
       updateStyleElement(storedTheme);
     } else {
       const styleElement = document.getElementById(