feat: synchronize account icons across game profiles

app/gateway-frontend/index.html

@@ -2,6 +2,7 @@
 <html lang="ko">
     <head>
         <meta charset="UTF-8" />
+        <meta name="color-scheme" content="dark" />
         <meta name="viewport" content="width=device-width, initial-scale=1.0" />
         <title>삼국지 모의전투 HiDCHe - Gateway</title>
     </head>