Add experimental comment to AsyncChunkSend

leaf-server/src/main/java/org/dreeam/leaf/config/modules/async/AsyncChunkSend.java

@@ -17,9 +17,11 @@ public class AsyncChunkSend extends ConfigModules {
     public void onLoaded() {
         config.addCommentRegionBased(getBasePath(),
             """
+                **Experimental feature**
                 Makes chunk packet preparation and sending asynchronous to improve server performance.
                 This can significantly reduce main thread load when many players are loading chunks.""",
             """
+                **实验性功能**
                 使区块数据包准备和发送异步化以提高服务器性能.
                 当许多玩家同时加载区块时, 这可以显著减少主线程负载.""");