Dubbo3.0如何对接istio+envoy的service mesh模式

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请问Dubbo3.0如何对接istio+envoy的service mesh模式。是关闭掉注册中心改为服务直连么？那么其中元数据中是否还需要？

How does Dubbo3.0 connect to istio+envoy service mesh mode? Close the registry and switch to direct service? Is it still needed in the metadata?

```JAVA
@DubboReference(url = "tri://myServiceName")
RpcService rpcService;
```

Start with the @DubboReference(url = "tri://myServiceName") entry point and review how Dubbo 3.0 handles service-mesh integration. Determine whether the registry and metadata are still required when using Istio and Envoy, then document a clear supported configuration and usage answer.

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