SpringBoot的application.yaml配置中超过两层的没提示

- [x] I have searched the [issues](https://github.com/apache/dubbo/issues) of this repository and believe that this is not a duplicate.

### Environment

* Dubbo version: 3.2.0
* Operating System version: Win11
* Java version: 1.8

### Steps to reproduce this issue


目测是dubbo的`@Nested`注解与spring的`@NestedConfigurationProperty`没有对齐

Pls. provide [GitHub address] to reproduce this issue.

### Expected Behavior

### Actual Behavior

If there is an exception, please attach the exception trace:

```
Just put your stack trace here!
```

Start by tracing Dubbo's nested configuration metadata handling and compare its @Nested annotation with Spring's @NestedConfigurationProperty, as suggested in the report. No source file or test is named; confirm the behavior for application.yaml properties more than two levels deep and verify that completion or提示 is restored without breaking existing configuration handling.

Written by the indexing model from the issue text.