Toggle Setting to Disable Sounds

Provide explicit toggle to disable sounds in settings.

Incorrect (no way to disable):

function App() {
  return <SoundProvider>{children}</SoundProvider>;
}

Correct (toggle available):

function App() {
  const { soundEnabled } = usePreferences();
  return (
    <SoundProvider enabled={soundEnabled}>
      {children}
    </SoundProvider>
  );
}