Images failing to load - Maybe large zip...

With this Manifest:

https://iiif.archive.org/iiif/b29000427_0001/manifest.json

the manifest generates OK but we get a 504 Gateway timeout when trying to access the first image:

https://iiif.archive.org/image/iiif/3/b29000427_0001%2Fb29000427_0001_jp2.zip%2Fb29000427_0001_jp2%2Fb29000427_0001_0001.jp2/info.json

and so it doesn't open in a viewer:

https://projectmirador.org/embed/?iiif-content=https://iiif.archive.org/iiif/b29000427_0001/manifest.json

This item is a book so the manifest generates quickly with the book reader API but it does have 1,293 pages:

https://archive.org/details/b29000427_0001

Reproduce the 504 by opening the provided info.json URL for the 1,293-page Internet Archive item, then compare it with the manifest and Mirador viewer behavior. Trace the IIIF image endpoint's handling of the large JP2 ZIP; done means the first image's info.json loads successfully and the manifest opens in the viewer without a gateway timeout.

Written by the indexing model from the issue text.