Consider deprecating old helpers API

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

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

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

Start by locating the configuration handling for `enable_notifications` and the existing data-notification entry point. Clarify which production events should trigger notifications and how users receive them. Done means the option defaults to `false`, enabling it produces the agreed notifications, and the behavior is covered by the relevant checks.

Written by the indexing model from the issue text.