Refactor Admin and Settings UI to Ethereal Precision aesthetic and improve note import/export functionality

memento-note/app/(main)/settings/ai/ai-settings-header.tsx

@@ -6,11 +6,9 @@ export function AISettingsHeader() {
   const { t } = useLanguage()
 
   return (
-    <div className="mb-6">
-      <h1 className="text-3xl font-bold">{t('aiSettings.title')}</h1>
-      <p className="text-gray-600 dark:text-gray-400">
-        {t('aiSettings.description')}
-      </p>
+    <div>
+      <h1 className="text-2xl font-bold tracking-tight text-foreground">{t('aiSettings.title')}</h1>
+      <p className="text-muted-foreground mt-1">{t('aiSettings.description')}</p>
     </div>
   )
 }