fix: update user guide layout for better readability

- Remove unnecessary paragraph breaks for a cleaner look
- Combine Chrome and Edge extension links into a single line
- Enhance overall structure of the user guide

Author: harryisfish

content/docs/user-guide/index.mdx

@@ -43,9 +43,6 @@ MultiPost 的愿景是通过自动化、AI、接口化，让内容创作者可
     * [multipost.app](https://multipost.app) - 官方网站 
   </span>
   <img src="https://img.shields.io/website?url=https%3A%2F%2Fmultipost.app" alt="MultiPost 网站" />
-</p>
-
-<p className="flex gap-2 flex-row items-center">
   <span>
     * [md.multipost.app](https://md.multipost.app/) - 文章编辑器 
   </span>
@@ -62,8 +59,7 @@ MultiPost 的愿景是通过自动化、AI、接口化，让内容创作者可
 </p>
 
 - [MultiPost 文章编辑器](https://md.multipost.app/) - [(代码仓库)](https://github.com/leaper-one/multipost-wechat-markdown-editor) - 用于创建和发布内容到多个平台的在线编辑器
-* [Chrome 扩展](https://chromewebstore.google.com/detail/multipost/dhohkaclnjgcikfoaacfgijgjgceofih)
-* [Edge 扩展](https://microsoftedge.microsoft.com/addons/detail/multipost/ckoiphiceimehjkolnfffgbmihoppgjg)
+* [Chrome 扩展](https://chromewebstore.google.com/detail/multipost/dhohkaclnjgcikfoaacfgijgjgceofih) | [Edge 扩展](https://microsoftedge.microsoft.com/addons/detail/multipost/ckoiphiceimehjkolnfffgbmihoppgjg)
 
 ## 文档更新