libimage: pass UID/GID mappings through the pull path

Propagate UIDMap/GIDMap from CopyOptions to SystemContext in NewCopier
so that the storage transport destination receives the mappings.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: giuseppe

common/libimage/copier.go

@@ -27,6 +27,7 @@ import (
 	"go.podman.io/image/v5/transports"
 	"go.podman.io/image/v5/types"
 	"go.podman.io/storage"
+	"go.podman.io/storage/pkg/idtools"
 )
 
 const (
@@ -150,6 +151,13 @@ type CopyOptions struct {
 	// an access token for the registry.
 	IdentityToken string `json:"identitytoken,omitempty"`
 
+	// ----- ID Mapping ---------------------------------------------------
+
+	// UIDMap and GIDMap are used for setting up image layers with the
+	// correct UID/GID mappings when pulling into storage.
+	UIDMap []idtools.IDMap
+	GIDMap []idtools.IDMap
+
 	// ----- internal -----------------------------------------------------
 
 	// Additional tags when creating or copying a docker-archive.
@@ -280,6 +288,9 @@ func NewCopier(options *CopyOptions, sc *types.SystemContext) (*Copier, error) {
 		c.systemContext.CompressionLevel = options.CompressionLevel
 	}
 
+	c.systemContext.UIDMap = options.UIDMap
+	c.systemContext.GIDMap = options.GIDMap
+
 	// NOTE: for the sake of consistency it's called Oci* in the CopyOptions.
 	c.systemContext.OCIAcceptUncompressedLayers = options.OciAcceptUncompressedLayers