支持 Ubuntu 一键部署与 PM2，并增加系统设置改密。

默认账号改为 admin/admin123，去掉 Windows 部署说明，与客户端同套部署流程。

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

templates/base.html

@@ -14,6 +14,7 @@
       <a href="/" class="{% if request.path == '/' %}active{% endif %}">总览</a>
       <a href="/instances" class="{% if request.path.startswith('/instances') %}active{% endif %}">实例</a>
       <a href="/desk" class="{% if request.path.startswith('/desk') %}active{% endif %}">工作台</a>
+      <a href="/settings" class="{% if request.path.startswith('/settings') %}active{% endif %}">系统设置</a>
       <a href="/logout">退出</a>
     </nav>
   </header>

templates/settings.html

@@ -0,0 +1,28 @@
+{% extends "base.html" %}
+{% block title %}系统设置 · 期权中控{% endblock %}
+{% block body %}
+<section class="page-head"><h1>系统设置</h1></section>
+
+<section class="panel settings-card">
+  <h2>登录账号</h2>
+  <p class="muted">修改后立即生效,并写入服务器 <code>.env</code>(<code>HUB_USERNAME</code> / <code>HUB_PASSWORD</code>).</p>
+  <form method="post" class="stack settings-form" autocomplete="off">
+    <label>当前用户名
+      <input type="text" value="{{ current_username }}" readonly class="readonly">
+    </label>
+    <label>当前密码
+      <input type="password" name="current_password" required autocomplete="current-password" placeholder="验证身份">
+    </label>
+    <label>新用户名
+      <input type="text" name="new_username" value="{{ current_username }}" required autocomplete="username" minlength="2" maxlength="64">
+    </label>
+    <label>新密码
+      <input type="password" name="new_password" autocomplete="new-password" minlength="6" placeholder="至少 6 位;不改密码可留空">
+    </label>
+    <label>确认新密码
+      <input type="password" name="confirm_password" autocomplete="new-password" minlength="6" placeholder="与新密码一致;不改密码可留空">
+    </label>
+    <button type="submit">保存账号</button>
+  </form>
+</section>
+{% endblock %}