Add rate limiting for monitoring

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

**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 hook and configuration handling in the Operator codebase, then clarify whether the requested behavior is rate limiting or notifications. Define the config scope, notification trigger, default behavior, and tests before implementation; done should include the agreed behavior working for production deployments.

Written by the indexing model from the issue text.