Photo controls don't encapsulate right

Summary: See the Lochleven inventory space. If I do "Create another Item" from an Item, and take a photo in that editor, the photo gets attached to the originating Thing, not the one being edited. That is, we're using the page identity, not the editor one, and they might be different.

This might be a special case of a general problem, but basically we are building the control too early, at page load when it should be at invocation.