Add TypeScript types for validation

**Feature request**
It would be great to have import for hooks.

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

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

The issue names no files, tests, or entry points. First locate the validation and configuration entry points, then clarify whether the goal is TypeScript types, hook imports, or the `enable_import` option; done should include the agreed behavior and default value.

Written by the indexing model from the issue text.