Add TypeScript types for core

**Feature request**
It would be great to have filtering for config.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_filtering` with default `false`.

The issue names no files or tests. Start by locating the core configuration entry point and its existing tests, then identify where the TypeScript types are defined. Done means the filtering option is represented there, defaults to false, and its behavior is covered by a focused test.

Written by the indexing model from the issue text.