feat: add note about campfire mode (#44118)

* feat: add note about campfire mode

* chore: shorter :)

Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>

Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>

client/src/components/settings/sound.tsx

@@ -19,6 +19,7 @@ export default function SoundSettings({
     <Form inline={true} onSubmit={(e: React.FormEvent) => e.preventDefault()}>
       <ToggleSetting
         action={t('settings.labels.sound-mode')}
+        explain={t('settings.sound-mode')}
         flag={sound}
         flagName='sound'
         offLabel={t('buttons.off')}