fix: update contact us section for clarity and consistency

- Add context to the support email for better user understanding.
- Include a description for the Tencent Channel link to enhance user engagement.

Author: harryisfish

content/docs/user-guide/contact-us.mdx

@@ -19,9 +19,9 @@ import tencentChannelWechatQna from '@/public/Tencent-Channel-Wechat-qna.png';
 ## 联系我们
 ### 联系开发组
 - [Discord](https://discord.gg/GNsCX9zFwQ)
-- support@leaper.one
+- support@leaper.one 如有问题可邮件联系。
 - [MultiPost Extension GitHub Issues](https://github.com/leaperone/MultiPost-Extension/issues)
-- [腾讯频道](https://pd.qq.com/s/e3ucjmz5g?b=9)
+- [腾讯频道](https://pd.qq.com/s/e3ucjmz5g?b=9) 如有疑问请加入频道。
 <div style={{display: 'flex', gap: '20px', flexDirection: {xs: 'column', sm: 'row', md: 'row'}}}>
   <div style={{width: '48%'}}>
     <p>QQ 扫一扫</p>