Improve data performance

**Feature request**
It would be great to have filtering for models.

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

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

No file, test, or entry point is named. Start by locating the model configuration and request-handling paths, then determine what model filtering should select and how enable_filtering is read. Done means the option defaults to false, enables the agreed filtering behavior when true, and is covered by tests.

Written by the indexing model from the issue text.