feat: 다운로드 관리 페이지에 fileHash 입력 필드 추가

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/admin/DownloadAdmin.jsx

@@ -4,7 +4,7 @@ import { apiFetch } from '../../api/client';
 import './AdminCommon.css';
 
 export default function DownloadAdmin() {
-  const [form, setForm] = useState({ url: '', version: '', fileName: '', fileSize: '' });
+  const [form, setForm] = useState({ url: '', version: '', fileName: '', fileSize: '', fileHash: '' });
   const [loading, setLoading] = useState(false);
   const [saved, setSaved] = useState(false);
 
@@ -15,6 +15,7 @@ export default function DownloadAdmin() {
         version: data.version,
         fileName: data.fileName,
         fileSize: data.fileSize,
+        fileHash: data.fileHash ?? '',
       }))
       .catch(() => {});
   }, []);
@@ -52,8 +53,9 @@ export default function DownloadAdmin() {
       <form className="admin-form" onSubmit={handleSubmit}>
         {field('다운로드 URL', 'url', 'https://...')}
         {field('버전', 'version', 'v1.0.0')}
-        {field('파일명', 'fileName', 'A301_Launcher.exe')}
+        {field('파일명', 'fileName', 'A301_Launcher.zip')}
         {field('파일 크기', 'fileSize', '1.2 GB')}
+        {field('A301.exe SHA256 해시', 'fileHash', 'sha256 해시값 (certutil -hashfile A301.exe SHA256)')}
         <div className="admin-form-actions">
           <button className="btn-admin-primary" type="submit" disabled={loading}>
             {saved ? '저장됨 ✓' : '저장'}