When bootc tries to copy the signed image from the host to the install disk it fails with the following error:

ERROR Installing to disk: Pulling from host storage: registry.redhat.io/amq-streams/kafka-37-rhel9:2.7.0-13: Subprocess failed: ExitStatus(unix_wait_status(32000))
Getting image source signatures
Checking if image destination supports signatures
Error: Copying this image would require changing layer representation, which we cannot do: "Would invalidate signatures"

Adding "--remove-signatures" to the podman image push command here fixes this error, however the result is an unsigned image. I did some digging through the containers/image code, skopeo docs, and containers-storage.conf docs. It looks like the only way to copy and sign an image is to re-sign the image when copying it, I couldn't find a way to copy a signed image while preserving the signature. I might be missing something though.