Add profile events for number of zookeeper

Why it matters

This feature provides enhanced observability into ZooKeeper interactions by counting the number of multi operations performed. It helps users monitor and analyze the usage of multi-read and multi-write requests to ZooKeeper, which can aid in performance tuning and diagnosing issues related to distributed coordination.

How to use it

After upgrading to the version containing this feature, users can access the new profile events related to ZooKeeper multi requests via existing system tables or monitoring tools that consume ClickHouse profile events. No additional configuration is required to enable these counters.