💄(frontend) make "more options" button more explicit

Change the "more options" button layout to horizontal orientation following
patterns used in Jitsi and Whereby. Improves discoverability and makes the
button's purpose more apparent to users.

src/frontend/src/features/rooms/livekit/components/controls/Options/OptionsButton.tsx

@@ -1,7 +1,7 @@
 import { useTranslation } from 'react-i18next'
-import { RiMore2Line } from '@remixicon/react'
+import { RiMoreFill } from '@remixicon/react'
 import { Button, Menu } from '@/primitives'
-import { OptionsMenuItems } from '@/features/rooms/livekit/components/controls/Options/OptionsMenuItems'
+import { OptionsMenuItems } from './OptionsMenuItems'
 
 export const OptionsButton = () => {
   const { t } = useTranslation('rooms')
@@ -15,7 +15,7 @@ export const OptionsButton = () => {
           aria-label={t('options.buttonLabel')}
           tooltip={t('options.buttonLabel')}
         >
-          <RiMore2Line />
+          <RiMoreFill />
         </Button>
         <OptionsMenuItems />
       </Menu>