Add configuration options for filtering

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

**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. Start by locating the configuration definitions and the existing authentication import path, then trace how configuration defaults are applied. Done means a disabled-by-default enable_import option controls the requested import behavior and its filtering effect is covered by the project's relevant checks.

Written by the indexing model from the issue text.