chore: 去掉 maxkb 聊天挂件

页面不再加载 maxkb 的嵌入脚本，删除对应的 PUBLIC_MAXKB_URL 配置。

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

client/.env.production

@@ -1,4 +1,3 @@
 PUBLIC_WEB_URL=https://web.xuyue.cc
 PUBLIC_BASE_URL=https://web.xuyue.cc/api
-PUBLIC_MAXKB_URL=https://maxkb.xuyue.cc/chat/api/embed?protocol=https&host=maxkb.xuyue.cc&token=df542e305f27dee6
 PUBLIC_ICONIFY_URL=https://icon.xuyue.cc

client/.env.staging

@@ -1,4 +1,3 @@
 PUBLIC_WEB_URL=http://10.13.114.114:91
 PUBLIC_BASE_URL=http://10.13.114.114:91/api
-PUBLIC_MAXKB_URL=http://10.13.114.114:92/chat/api/embed?protocol=http&host=10.13.114.114:92&token=df542e305f27dee6
 PUBLIC_ICONIFY_URL=http://10.13.114.114:8098

client/index.html

@@ -7,16 +7,6 @@
     <title>前端开发学习平台</title>
     <link rel="stylesheet" href="/normalize.min.css" />
     <link rel="stylesheet" href="/style.css" />
-    <script>
-      window.localStorage.setItem("maxkbMaskTip", true)
-    </script>
-    <% if (process.env.PUBLIC_MAXKB_URL) { %>
-    <script
-      async
-      defer
-      src="<%= process.env.PUBLIC_MAXKB_URL %>"
-    ></script>
-    <% } %>
   </head>
   <body>
     <div id="app"></div>

client/src/env.d.ts

@@ -1,7 +1,6 @@
 interface ImportMetaEnv {
   readonly PUBLIC_WEB_URL: string
   readonly PUBLIC_BASE_URL: string
-  readonly PUBLIC_MAXKB_URL: string
   readonly PUBLIC_ICONIFY_URL: string
   readonly PUBLIC_WS_URL: string
 }