Investigate how to nest components

The new `JSONViewer` component introduced in #49 is rendered within the `Home` component. The `App` component has no knowledge of its existence, so `JSONViewer` is dependent upon specific logic within `Home` to call `json_viewer.update` and `json_viewer.register_action_handler`

This works, but it does not scale. As more components are added to `Home` this custom logic will grow in size and complexity.

Should `Home` have a property of `components` similar to `App` that contains all components that require wiring? Alternatively, should the component instead be surfaced to `App`, and then `Home` just needs to call `render` on any nested components?

Please investigate a recommended approach