Implement ordered pipeline step resolution

internal/framework/pipeline/validator_chain_registry.go

@@ -92,9 +92,9 @@ func cloneModuleBinding(binding ModuleBinding) ModuleBinding {
 	binding.LLMProfile = strings.TrimSpace(binding.LLMProfile)
 	binding.Options = cloneOptions(binding.Options)
 	if len(binding.References) > 0 {
-		references := make(map[string]string, len(binding.References))
+		references := make(map[string]ReferenceSource, len(binding.References))
 		for key, value := range binding.References {
-			references[key] = value
+			references[key] = cloneReferenceSource(value)
 		}
 		binding.References = references
 	}
@@ -102,6 +102,15 @@ func cloneModuleBinding(binding ModuleBinding) ModuleBinding {
 	return binding
 }
 
+func cloneReferenceSource(source ReferenceSource) ReferenceSource {
+	out := source
+	if source.Artifact != nil {
+		artifact := *source.Artifact
+		out.Artifact = &artifact
+	}
+	return out
+}
+
 func cloneValidatorOverride(override ValidatorOverride) ValidatorOverride {
 	return ValidatorOverride{
 		Set:        override.Set,