crane: Rebase give inconsistent layer types if the original image and new base use different layer types

### Describe the bug

The image resulting from a rebase in which the original image and new base don't have the same layer types is not usable.

### To Reproduce

1. Create an image using `application/vnd.docker.image.rootfs.diff.tar.gzip` layer type. For example, an image produced by Jib.
2. Rebase it on a base using `application/vnd.oci.image.layer.v1.tar+gzip` layer type. (It could be the same base as the Jib image.)
3. The resulting image has OCI layer types on top of Docker layer types and is unusable.

_Edit: the image is unusable with `podman run`, but seems to work when using `docker run`._

### Expected behavior

The rebase should normalize the layer types so that the resulting image is usable.

Start at the crane rebase entry point and inspect how layer media types are retained when combining the original image with the new base. Reproduce the case with Docker and OCI layer types, then verify that the rebased image uses normalized layer types and runs with podman.

Written by the indexing model from the issue text.