docs(readme): add star/watch buttons and guidance to first screen

The badge row had no star or watch affordance. Adds social-style badges and a
one-line note under the intro explaining why starring matters and how to watch
releases only, in both language versions.

README_zh.md

@@ -14,6 +14,9 @@
 [![Java](https://img.shields.io/badge/java-21-ED8B00?logo=openjdk&logoColor=white)](https://openjdk.org/projects/jdk/21/)
 [![React](https://img.shields.io/badge/react-19-61DAFB?logo=react&logoColor=black)](https://react.dev)
 
+[![GitHub Stars](https://img.shields.io/github/stars/iflytek/skillhub?style=social)](https://github.com/iflytek/skillhub/stargazers)
+[![GitHub Watchers](https://img.shields.io/github/watchers/iflytek/skillhub?style=social)](https://github.com/iflytek/skillhub/watchers)
+
 </div>
 
 ---
@@ -24,6 +27,8 @@
 
 SkillHub 是一个自托管平台，为团队提供私有的、受治理的智能体技能共享空间。发布技能包，推送到命名空间，让其他人通过搜索发现或通过 CLI 安装。专为防火墙后的本地部署而构建，提供与公共注册中心相同的精致体验。
 
+> ⭐ 如果 SkillHub 适合你的团队，欢迎 **Star** 本仓库帮助更多团队发现它；点 **Watch → Custom → Releases** 可在新版本发布时收到通知。
+
 ## 文档
 
 - 📖 **[用户指南](https://iflytek.github.io/skillhub/)** — 技能发布、搜索、CLI 使用等用户操作指南