Support for PostgreSQL Generated Columns in MaterializedPostgreSQL

Why it matters

This feature enables ClickHouse to correctly interpret and handle PostgreSQL tables that use generated columns and default values, providing better compatibility and more accurate data representation when replicating or migrating data from PostgreSQL to ClickHouse.

How to use it

To use this feature, enable the experimental support for generated columns and default values when creating or syncing tables with the MaterializedPostgreSQL engine. This is managed automatically when replicating PostgreSQL tables that have these column attributes.