Add unit tests for routes

**Feature request**
It would be great to have caching for components.

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

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

The title asks for unit tests for routes, while the body requests component caching through a new enable_caching option. No files, tests, or entry points are named; first reconcile the scope and locate the route, component, and configuration entry points. Done should include agreed coverage for the requested behavior and confirm the option defaults to false.

Written by the indexing model from the issue text.