Allow JSON-esque outputs through `str/repr`

[databyjp]

Some users have queried how they can produce a JSON-type output in the v4 API.

It may be a nice QoL improvement if this was possible, e.g. through a str/repr function or something like a to_dict() method. Not yet clear what this should look like / how much information this should print to balance verbosity and convenience.

[mjsteele12]

This would be amazing, especially for results with cross references.