feat(meowpanel): 可选密码鉴权 (agent-196, 用户定案) — panel.auth_enabled(默认0)+panel.auth_pass(带盐sha256不明文); token会话(/dev/urandom,TTL12h,内存+卡持久化,静态屏蔽session文件); 未启用零回归,启用后 /api/* 全要会话; 前端登录页+401回跳+设置卡片; 顺带修 settings_write_one 容忍等号两侧空格(原会重复追加行)

meowpanel→f91856a4; 0 warning; 宿主curl 20例+headless Chromium 全过

patch_v2/meowpanel/web/index.html

@@ -100,6 +100,30 @@
   </div>
 </div>
 
+<!-- 登录页（面板鉴权启用后显示） -->
+<div id="login" class="login-scrim" hidden>
+  <div class="login-box">
+    <div class="login-brand"><span class="login-brand-mark">M</span><span>MeowPanel</span></div>
+    <p class="login-sub">此面板已开启密码鉴权，请输入密码后使用。</p>
+    <input type="password" id="login-password" class="login-input" placeholder="面板密码" autocomplete="current-password">
+    <p class="login-err" id="login-err" hidden></p>
+    <button class="btn btn-primary login-btn" id="login-btn">登 录</button>
+  </div>
+</div>
+
+<!-- 设置面板密码对话框 -->
+<div id="pwdlg" class="modal-scrim" hidden>
+  <div class="modal">
+    <h2 class="modal-title" id="pwdlg-title">设置面板密码</h2>
+    <p class="modal-body" id="pwdlg-body">请输入新密码（留空则清除密码）。</p>
+    <input type="password" id="pwdlg-input" class="login-input" placeholder="新密码" autocomplete="new-password">
+    <div class="modal-actions">
+      <button class="btn" id="pwdlg-cancel">取消</button>
+      <button class="btn btn-primary" id="pwdlg-ok">确定</button>
+    </div>
+  </div>
+</div>
+
 <div id="toast" class="toast" hidden></div>
 
 <script src="meowpanel.js"></script>