[Improvement] improvement Dispatcher mechanism

### What would you like to be improved?

Currently we need to wrap `Dispatcher` too many times.

https://github.com/apache/gravitino/blob/main/core/src/main/java/org/apache/gravitino/GravitinoEnv.java#L351
```
MetalakeDispatcher metalakeManager = new MetalakeManager(entityStore, idGenerator);
MetalakeNormalizeDispatcher metalakeNormalizeDispatcher =
new MetalakeNormalizeDispatcher(installDispatcherHooks(metalakeManager));
this.metalakeDispatcher = new MetalakeEventDispatcher(eventBus, metalakeNormalizeDispatcher);
```
I think we can improvement `Dispatcher` mechanism in the future.

+ https://github.com/apache/gravitino/pull/4429#discussion_r1709314924

### How should we improve?

_No response_

Start with the Dispatcher construction in core/src/main/java/org/apache/gravitino/GravitinoEnv.java around line 351, then read the referenced discussion in PR 4429. Trace how MetalakeManager, MetalakeNormalizeDispatcher, and MetalakeEventDispatcher are composed. Done should mean a clearer Dispatcher mechanism that reduces repeated wrapping while preserving the existing behavior.

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