Typo in package name: uitl should be util

The package `org.apache.rocketmq.a2a.common.uitl` is misspelled.
`uitl` should be `util`.

This affects:
- src/main/java/.../common/uitl/RequestIdGenerator.java
- src/main/java/.../common/uitl/RocketMQUtil.java
- Import statements in RocketMQTransport.java, RocketMQA2AServerRoutes.java,
and example modules

Start by locating the common/uitl package and its RequestIdGenerator.java and RocketMQUtil.java files, then inspect imports in RocketMQTransport.java, RocketMQA2AServerRoutes.java, and the example modules. Rename the package to common/util and update the affected imports; the work is done when the old package name no longer appears and the project builds successfully.

Written by the indexing model from the issue text.