docs: update WeChat QR to group 5 (#10126)

All earlier WeChat groups are full; point the README QR and copy at group 5.

README.md

@@ -238,7 +238,7 @@ Pair with your desktop app to monitor and steer your agents from your phone.
 
 - **Discord:** Join the community on **[Discord](https://discord.gg/fzjDKHxv8Q)**.
 - **Twitter / X:** Follow **[@orca_build](https://x.com/orca_build)** for updates and announcements.
-- **WeChat:** Groups 1 and 2 are both full — now you can join the third one.
+- **WeChat:** All other groups are full, now we're on group 5.
 
   <img src="docs/assets/wechat-qr.jpg" alt="WeChat QR code for the Orca community" width="160" />
 

docs/readme/README.zh-CN.md

@@ -235,7 +235,7 @@ yay -S stably-orca-bin
 
 - **Discord:** 加入 **[Discord](https://discord.gg/fzjDKHxv8Q)** 社区。
 - **Twitter / X:** 关注 **[@orca_build](https://x.com/orca_build)** 获取更新和公告。
-- **微信:** 第一、二个微信群均已满，现在可以加入第三个群。
+- **微信:** 其他群已满，现在加入第 5 群。
 
   <img src="../assets/wechat-qr.jpg" alt="Orca 社区微信群二维码" width="160" />