Update wechat QR codes and add spacing between them in README

- Refresh star-history chart and backup WeChat QR image assets
- Add spacing between the primary and backup WeChat QR codes in both README.md and README.zh-CN.md

README.md

@@ -241,6 +241,7 @@ Pair with your desktop app to monitor and steer your agents from your phone.
 - **WeChat:** Scan the QR code to join the community. If the first group is full, use the backup group.
 
   <img src="docs/assets/wechat-qr.png" alt="WeChat QR code for the Orca community" width="160" />
+  &nbsp;&nbsp;&nbsp;
   <img src="docs/assets/wechat-qr-backup.jpg" alt="Backup WeChat QR code for the Orca community" width="160" />
 
 - **Feedback &amp; Ideas:** We ship fast. Missing something? [Request a new feature](https://github.com/stablyai/orca/issues).

docs/readme/README.zh-CN.md

@@ -238,6 +238,7 @@ yay -S stably-orca-bin
 - **微信:** 扫描二维码加入社区。如果第一个群已满，请使用备用微信群。
 
   <img src="../assets/wechat-qr.png" alt="Orca 社区微信群二维码" width="160" />
+  &nbsp;&nbsp;&nbsp;
   <img src="../assets/wechat-qr-backup.jpg" alt="Orca 社区备用微信群二维码" width="160" />
 
 - **反馈与想法:** 我们发布很快。缺少什么功能？[提交功能请求](https://github.com/stablyai/orca/issues)。