Check if image exists before deleting civs for archive items

[amickan]

When uploading a new image to an existing archive item, all non-image CIVs of that same item used to get deleted. The reason for this was that we checked for existing CIVs with the same image and deleted those. In the case of new image uploads, however, civ.image is still empty at the time of checking, and so it matched all CIVs with image=None.

I was confused why we need this check at all. After some digging, I realized that it's necessary to enable updating of the interface of an image through the api (say from generic medical image to something more specific). This was a common use case when it was added. I'm in doubt whether we still need or want to offer this feature. It means that you can never have an archive item with the same image attached to different interfaces. Seems like a reasonable restriction to me, but it's a restriction that we don't enforce anywhere else (i.e. for display sets or jobs) as far as I know.

Finally, adding a new interface to an archive item through the dropdown menu no longer worked since it used inline js. Fixed that as well.

Closes #3104

[jmsmkn]

It means that you can never have an archive item with the same image attached to different interfaces. Seems like a reasonable restriction to me, but it's a restriction that we don't enforce anywhere else (i.e. for display sets or jobs) as far as I know.

Test it out, I don't think that restriction is necessary. If we do allow this, do users have an easy way of removing values from a display set?

[amickan]

Test it out, I don't think that restriction is necessary. If we do allow this, do users have an easy way of removing values from a display set?

It's possible to attach the same image twice to one display set (with different interfaces of course), and no, users cannot delete images from display sets. Deleting only works for everything else. Enabling that would require some changes to the FlexibleImageWidget, which we use in multiple places, so we would need to be careful with making changes.