Support for additional_table_filters and additional_result_filter in new planner with documentation update

Why it matters

This feature enables users to apply extra filtering conditions at both the table scan and query result stages within the new planner. It enhances query flexibility and control, allowing more precise data filtering during execution.

How to use it

Users can enable these filters by setting the additional_table_filters and/or additional_result_filter settings in their queries or server configuration. These settings allow specifying additional WHERE-like conditions that are applied during query processing using the new planner.