feat(saju-ui-v2): saju.desktop.jsx — 4탭 유지 + max-width 900 컨테이너

src/pages/saju/views/saju.desktop.jsx

@@ -0,0 +1,10 @@
+import React from 'react';
+import SajuMobile from './saju.mobile.jsx';
+
+export default function SajuDesktop({ reading }) {
+  return (
+    <div style={{ maxWidth: 900, margin: '0 auto' }}>
+      <SajuMobile reading={reading} />
+    </div>
+  );
+}