Remove `InternalsVisibleTo` dependency between Container Registry package and `Aspire.Hosting.Azure`

The container registry package currently relies on `InternalsVisibleTo` (IVT) access to `Aspire.Hosting.Azure` to acquire internal Azure-specific types needed for authenticating with Azure Container Registries. This creates an undesirable coupling between the generic container registry abstractions and Azure-specific hosting logic.

This coupling makes it difficult to evolve the Azure hosting package independently, and it prevents other cloud-specific registry implementations from following a clean extension model.