fix: restore Netpoll project card on ZH homepage

Agent-Logs-Url: https://github.com/cloudwego/cloudwego.github.io/sessions/72e8df2c-9f71-441e-9d0f-1fb867f43a2d

Co-authored-by: GuangmingLuo <16001996+GuangmingLuo@users.noreply.github.com>

Author: Copilot

content/zh/_index.html

@@ -76,6 +76,12 @@ <h2>Hertz</h2>
             <p>下一代高性能、强可扩展的 Go HTTP 框架。</p>
         </a>
     </div>
+    <div class="col-md-3 col-sm-6 col-xs-12 home-project-item">
+        <a href="https://github.com/cloudwego/netpoll">
+            <h2>Netpoll</h2>
+            <p>高性能、I/O非阻塞的网络框架，专注于 RPC 场景。</p>
+        </a>
+    </div>
     <div class="col-md-3 col-sm-6 col-xs-12 home-project-item">
         <a href="https://github.com/cloudwego/volo">
             <h2>Volo</h2>