备份时写入当前中控登录用户名和密码，恢复后可直接使用。

Co-authored-by: Cursor <cursoragent@cursor.com>

templates/settings.html

@@ -103,7 +103,7 @@
         <div class="backup-block">
           <div class="backup-block-head">
             <h3>中控备份</h3>
-            <p class="muted field-hint">目录 <code id="hub-backup-dir">/root/crypto_okx_hub_backups</code> · 含 <code>.env</code> 与 <code>hub.db</code>。换机时先上传家里下载的包，再点恢复。</p>
+            <p class="muted field-hint">目录 <code id="hub-backup-dir">/root/crypto_okx_hub_backups</code> · 含 <code>.env</code>、<code>hub.db</code>、当前登录用户名和密码。换机时先上传家里下载的包，再点恢复。</p>
             <div class="settings-actions">
               <button type="button" class="settings-primary" id="hub-backup-create">立即备份</button>
               <button type="button" class="btn-secondary" id="hub-backup-refresh">刷新</button>
@@ -188,7 +188,7 @@
 </div>
 {% endblock %}
 {% block scripts %}
-<script src="{{ url_for('static', filename='settings_backup.js') }}?v=3"></script>
+<script src="{{ url_for('static', filename='settings_backup.js') }}?v=4"></script>
 <script src="{{ url_for('static', filename='settings_update.js') }}?v=5"></script>
 <script>
   HubSettingsBackup.boot();