Support IIIF Image 3 embedded within Presentation 2 manifests

https://redmine.teklia.com/issues/10642

I cannot find any official documentation or examples on the mix of IIIF Image 3.x with IIIF Presentation 2.x, nor any examples anywhere on GitHub. We only have the few examples we got from Nakala.

But because of the very basic way we parse IIIF manifests, and because we will rely on the backend to auto-detect which IIIF version is used for each image, the IIIF import should be able to grab IIIF 3 images by looking for canvas.images[0].resource.service.id first, then fall back to .@id for IIIF 2.