[Question] Support querying via prometheus for rocketMQ

### Question

According to [the doc](https://rocketmq.apache.org/docs/observability/01metrics/), rocketMQ is supported for querying metrics using the Prometheus protocol. Currently the code seems to use the method of creating an instance to query information (https://github.com/apache/hertzbeat/pull/1046), so the metrics that could be queried seems limited and its a waste of connection resource. I think it is necessary to support querying via prometheus for rocketMQ.

btw, I'm not sure if I should create a [Task], so I just create a [Question].

Start with the RocketMQ metrics documentation linked in the issue and the existing implementation introduced by pull request #1046. Determine the intended Prometheus-query path and its scope before identifying the relevant monitoring entry points; done means RocketMQ metrics can be queried through Prometheus rather than only through the current instance-based method.

Written by the indexing model from the issue text.