How do I share media between items?

[SteveScott]

@braulio.balanza

It took me a while to figure out that the ref in the `data` object has to be prefixed with `api::`. Would this be, more or less, what you are trying to accomplish?

@braulio.balanza, @dmehaffy
I am now able to upload a file. But I am not sure how to link it to an item in a collection. I could take the URL of the media (I store it on Azure) and save it as a URL on the object. But that doesn’t seem right; it is a URL, not a media object, and I can only assign one, not a collection. How do I assign a previously-uploaded media file to a field of type media, assuming I have the data from the upload post response?