Virtual transport of RocketMQ

[imzs]

Hi all,

This PR aims to add support for RocketMQ as a new transport option in Kombu. The need for this integration was driven by a user's request to incorporate RocketMQ into their Celery-powered applications, which led to the initial implementation.

This PR adds kombu.transport.rocketmq as a pluggable transport , supports for core messaging operations including publish, consume, and acknowledgment.

Any feedback, suggestions will be truly appreciated to ensure it aligns with Kombu’s architecture, coding standards, and long-term maintenance goals.