Image Streams Don't Resolve To Be Cached

When `getUncachedImageStream` cannot resolve the URL, it will use Image dimensions `1, 1` instead of being omitted or using/returning `0, 0`. This means the Canvases with these images are all `1000, 1000` and the images themselves are all `1, 1` in the Manifests, which will absolutely wreck all attempts at interoperability. However, somehow the TPEN interface manages because after some time it does resolve the image.

Our best idea, already referenced in #703, is to let the interface detect this scenario and after it loads the images and has dimensions to update the cached dimensions for the folio (per folio, one at a time, as the interface resolves the image so the user will not experience any extra delay).

Start at the getUncachedImageStream entry point and read the discussion in #703 to understand how unresolved image URLs currently produce dimensions. Trace how those dimensions reach canvases and manifests, then verify that unresolved images are not recorded as 1,1 and that resolved dimensions can update the cached folio values one folio at a time.

Written by the indexing model from the issue text.