Consider deprecating old data API

**Feature request**
It would be great to have search for services.

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

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

No files, tests, or entry points are identified in the issue. First reconcile the title's deprecation request with the body’s service-search request, then locate the configuration and service-discovery entry points; done should be defined as an agreed scope, including the behavior of enable_search when its default is false.

Written by the indexing model from the issue text.