Use a proper image name for the imported tar image

When an image is imported from tar without an annotation for the image
name, we generate a fake one. Make sure it is valid.

Author: adam-rl

cmd/convertor/builder/content_store_resolver.go

@@ -149,7 +149,7 @@ func NewContentStoreResolverFromTar(ctx context.Context, tarPath string) (*Conte
 			log.G(ctx).Debugf("  📁 FOUND IMAGE INDEX: Importing as-is for multi-arch conversion")
 
 			// Import the index itself - let the builder handle platform traversal
-			ref := fmt.Sprintf("imported:%s", manifest.Digest.Encoded()[:12])
+			ref := fmt.Sprintf("local/imported:%s", manifest.Digest.Encoded()[:12])
 			if manifest.Annotations != nil {
 				if name, ok := manifest.Annotations["org.opencontainers.image.ref.name"]; ok {
 					ref = name
@@ -169,7 +169,7 @@ func NewContentStoreResolverFromTar(ctx context.Context, tarPath string) (*Conte
 		log.G(ctx).Debugf("  ✅ PROCESSING: Regular container manifest")
 
 		// Generate a reference name for the imported image
-		ref := fmt.Sprintf("imported:%s", manifest.Digest.Encoded()[:12])
+		ref := fmt.Sprintf("local/imported:%s", manifest.Digest.Encoded()[:12])
 		if manifest.Annotations != nil {
 			if name, ok := manifest.Annotations["org.opencontainers.image.ref.name"]; ok {
 				ref = name

cmd/convertor/main.go

@@ -150,7 +150,7 @@ Version: ` + commitID,
 				for _, img := range images {
 					// The main index usually has the original tag name (e.g., "latest")
 					// Platform-specific manifests have names like "latest-linux-amd64"
-					if !strings.Contains(img.Name, "-linux-") && !strings.Contains(img.Name, "imported:") {
+					if !strings.Contains(img.Name, "-linux-") && !strings.Contains(img.Name, "local/imported:") {
 						ref = img.Name
 						isMultiArch = (img.Target.MediaType == "application/vnd.oci.image.index.v1+json")
 						break