Send a multipart/form-data request containing the file in the body, and pass the media
type as a query string parameter: ?media_type=image.

The file is stored exactly as an upload made inside Loop, so it appears in the Loop UI and
in outbound portal feeds. The new item takes the last order position within its media
type.

File names must be unique within a property and media type — the name forms part of the
storage path, so a repeat name is rejected rather than allowed to overwrite the first file.
Spaces in the name become dashes. A property can hold at most 99 images; the other media
types are uncapped.