Add system settings, one-click deploy, and simplify embed UI.

Remove Gate scout auto-seeding and the manual hub login button while keeping Gate login and instance SSO. Add password change and database backup/restore, plus deploy scripts with env auto-generation.

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

templates/admin_groups.html

@@ -6,6 +6,7 @@
   <nav>
     <a href="{{ url_for('index') }}">返回导航</a>
     <a href="{{ url_for('admin_services') }}">服务管理</a>
+    <a href="{{ url_for('admin_settings') }}">系统设置</a>
     <a href="{{ url_for('logout') }}">退出</a>
   </nav>
 </header>