Support window function expressions in ClickHouse

Why it matters

This feature enables the use of window functions directly within expressions, allowing more advanced and flexible analytical queries. It solves the limitation of not being able to combine window functions seamlessly inside expressions, improving query expressiveness and performance for analytical workloads.

How to use it

Users can now include window functions inside expressions in their SQL queries. For example, you can use window functions within the SELECT clause or WITH expressions as part of complex calculations and aggregations.