docs: point community Discord to the official HKUDS server

Re-add the Discord badge (5 READMEs) and an issue-template contact removed
in 8346def, now pointing at the org-controlled HKUDS community server
(discord.gg/6TdQnT5xcF, guild 1296348098003734629, ~1.9k members) — the same
server linked from the HKUDS org profile and LightRAG — instead of the
compromised invite. Keeps GitHub Discussions as a second contact.

.github/ISSUE_TEMPLATE/config.yml

@@ -1,5 +1,8 @@
 blank_issues_enabled: true
 contact_links:
+  - name: Discord Community
+    url: https://discord.gg/6TdQnT5xcF
+    about: Join the HKUDS community Discord
   - name: GitHub Discussions
     url: https://github.com/HKUDS/Vibe-Trading/discussions
     about: Ask questions, share strategies, get help

README.md

@@ -25,6 +25,7 @@
   <br>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/Feishu-Group-E9DBFC?style=flat-square&logo=feishu&logoColor=white" alt="Feishu"></a>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/WeChat-Group-C5EAB4?style=flat-square&logo=wechat&logoColor=white" alt="WeChat"></a>
+  <a href="https://discord.gg/6TdQnT5xcF"><img src="https://img.shields.io/badge/Discord-Join-7289DA?style=flat-square&logo=discord&logoColor=white" alt="Discord"></a>
 </p>
 
 <p align="center">

README_ar.md

@@ -25,6 +25,7 @@
   <br>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/Feishu-Group-E9DBFC?style=flat-square&logo=feishu&logoColor=white" alt="Feishu"></a>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/WeChat-Group-C5EAB4?style=flat-square&logo=wechat&logoColor=white" alt="WeChat"></a>
+  <a href="https://discord.gg/6TdQnT5xcF"><img src="https://img.shields.io/badge/Discord-Join-7289DA?style=flat-square&logo=discord&logoColor=white" alt="Discord"></a>
 </p>
 
 <p align="center">

README_ja.md

@@ -25,6 +25,7 @@
   <br>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/Feishu-Group-E9DBFC?style=flat-square&logo=feishu&logoColor=white" alt="Feishu"></a>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/WeChat-Group-C5EAB4?style=flat-square&logo=wechat&logoColor=white" alt="WeChat"></a>
+  <a href="https://discord.gg/6TdQnT5xcF"><img src="https://img.shields.io/badge/Discord-Join-7289DA?style=flat-square&logo=discord&logoColor=white" alt="Discord"></a>
 </p>
 
 <p align="center">

README_ko.md

@@ -25,6 +25,7 @@
   <br>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/Feishu-Group-E9DBFC?style=flat-square&logo=feishu&logoColor=white" alt="Feishu"></a>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/WeChat-Group-C5EAB4?style=flat-square&logo=wechat&logoColor=white" alt="WeChat"></a>
+  <a href="https://discord.gg/6TdQnT5xcF"><img src="https://img.shields.io/badge/Discord-Join-7289DA?style=flat-square&logo=discord&logoColor=white" alt="Discord"></a>
 </p>
 
 <p align="center">

README_zh.md

@@ -25,6 +25,7 @@
   <br>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/Feishu-Group-E9DBFC?style=flat-square&logo=feishu&logoColor=white" alt="Feishu"></a>
   <a href="https://github.com/HKUDS/.github/blob/main/profile/README.md"><img src="https://img.shields.io/badge/WeChat-Group-C5EAB4?style=flat-square&logo=wechat&logoColor=white" alt="WeChat"></a>
+  <a href="https://discord.gg/6TdQnT5xcF"><img src="https://img.shields.io/badge/Discord-Join-7289DA?style=flat-square&logo=discord&logoColor=white" alt="Discord"></a>
 </p>
 
 <p align="center">