Support SELECT ... INTO OUTFILE and STDOUT in ClickHouse

Why it matters

This feature enables users to export query results directly into files or stream them to standard output, simplifying data export workflows and improving integration capabilities with other tools or scripts.

How to use it

Use the SELECT ... INTO OUTFILE 'filepath' syntax to save query results directly to a specified file. To stream results, use the STDOUT option as part of the INTO OUTFILE clause.