[Enhancement] General code simplification

### Search before asking

- [X] I had searched in the [issues](https://github.com/apache/eventmesh/issues?q=is%3Aissue) and found no similar issues.

### Enhancement Request

org/apache/eventmesh/common/EventMeshThreadFactory.java, ThreadPoolFactory.java
org/apache/eventmesh/common/protocol/grpc/common/BatchMessageWrapper.java, SimpleMessageWrapper.java
org/apache/eventmesh/common/protocol/http/HttpCommand.java, HttpEventWrapper.java
org/apache/eventmesh/common/protocol/tcp/Package.java

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Use lombok simplify class def.

Extract the same code logic.

Remove unnecessary modifier in ThreadPoolFactory.

Use `Maps.newHashMap` to simplify init a map.

### Describe the solution you'd like

Use lombok simplify class def.

Extract the same code logic.

Remove unnecessary modifier in ThreadPoolFactory.

Use `Maps.newHashMap` to simplify init a map.

### Are you willing to submit PR?

- [X] Yes I am willing to submit a PR!

Review the listed classes under org/apache/eventmesh/common and its protocol/grpc, http, and tcp subpackages, starting with the repeated class and initialization patterns. Apply the requested Lombok simplification, shared-logic extraction, modifier removal, and map initialization changes across those files, then verify the project still builds and tests pass.

Written by the indexing model from the issue text.