Add Query Capability for Distributed over Distributed Without distributed_group_by_no_merge

Why it matters

This feature solves the limitation where querying Distributed tables over other Distributed tables was restricted or required special settings. It enables more flexible and efficient querying of nested Distributed tables, simplifying distributed query processing and improving user experience.

How to use it

Users can now directly SELECT from Distributed tables that reference other Distributed tables without enabling the distributed_group_by_no_merge setting. The feature works by default once the new ClickHouse version is deployed.