Add feedback-aware correction contracts

internal/framework/pipeline/runner.go

@@ -499,6 +499,9 @@ func (r *Runner) validateChunks(ctx context.Context, doc *source.SourceDocument,
 		default:
 			return nil, nil, fmt.Errorf("validator %q is incompatible with chunk validation", binding.Module)
 		}
+		if err == nil {
+			err = contracts.ValidateValidationResult(result)
+		}
 		debugContent := debugContentEnvelope(content, "application/json", nil, nil)
 		debugContent.ContentDigest = debugContentDigest(content)
 		debugCall := debugValidationCall{ValidatorName: binding.Module, Request: map[string]any{"stage": string(StageChunk), "module_key": moduleKey, "source_id": doc.ID, "schema": schema, "schema_digest": contracts.DigestArtifactSchema(schema), "content": debugContent, "metadata": redactSensitiveMap(metadata)}, Result: debugValidationResultEnvelope(result)}