Add artifact reading and output validation

internal/validate/validator.go

@@ -0,0 +1,16 @@
+package validate
+
+import (
+	"context"
+	"gitea.maximumdirect.net/eric/promptkit/internal/domain"
+)
+
+// Validator validates the generated artifact based on the output contract.
+type Validator interface {
+	Validate(ctx context.Context, artifact *domain.Artifact, contract domain.OutputContract) (domain.ValidationResult, error)
+}
+
+// SchemaDocumentLoader loads JSON schema documents using validator path semantics.
+type SchemaDocumentLoader interface {
+	LoadSchemaDocument(ctx context.Context, schemaPath string) (any, error)
+}