Document retry composition and preserve error summaries

internal/framework/llm/scheduled_client.go

@@ -38,7 +38,7 @@ func (c *scheduledClient) CompleteStructured(ctx context.Context, req contracts.
 		return callErr
 	})
 	if err != nil {
-		return contracts.StructuredCompletionResponse{}, err
+		return response, err
 	}
 	return response, nil
 }