Consider deprecating old components API

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

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

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

No files, tests, or entry points are identified. First reconcile the title's proposed deprecation of the old components API with the body’s request for type notifications and an `enable_notifications` option; then locate the configuration entry point and define the expected behavior and completion criteria.

Written by the indexing model from the issue text.