How to know if route loaded as node or parent?

[spq-easy]

I have a route like project/requests and a child route project/requests/$request_id. If project/requests is loaded as a view I want to show a form for submitting a new request. If project/requests/$request_id is loaded, it should instead show the details of that request. I have not found an easy way to determine this usage in the parent so I can optionally show the form or load a new request form component.

[schiller-manuel]

add an project/requests/index route