UNO refactor: panel-ize Auth card + Room friend-picker modal

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/components/screens/AuthScreen.tsx

@@ -16,7 +16,7 @@ export function AuthScreen() {
   return (
     <ScreenShell hideNav>
       <ScreenHeader title={t("auth.title")} />
-      <div className="glass rounded-3xl p-6 max-w-md mx-auto">
+      <div className="panel rounded-3xl p-6 max-w-md mx-auto mt-6">
         <p className="text-center text-cream/60 text-sm mb-5">{t("auth.subtitle")}</p>
 
         {/* Active method: phone OTP */}

src/components/screens/RoomScreen.tsx

@@ -145,7 +145,7 @@ export function RoomScreen() {
               animate={{ y: 0, opacity: 1 }}
               exit={{ y: 40, opacity: 0 }}
               onClick={(e) => e.stopPropagation()}
-              className="glass rounded-3xl p-5 w-full max-w-sm max-h-[70vh] overflow-y-auto"
+              className="panel rounded-3xl p-5 w-full max-w-sm max-h-[70vh] overflow-y-auto"
             >
               <h3 className="text-lg font-black gold-text mb-3">{t("room.pickFriend")}</h3>
               <div className="space-y-2">