Add rate limiting for import

**Feature request**
It would be great to have notifications for middleware.

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

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

The issue names no file, test, or entry point. First clarify whether the request concerns import rate limiting or middleware notifications, then identify the affected configuration and test location. The only stated completion detail is an enable_notifications option with a default of false.

Written by the indexing model from the issue text.