Present native PromptKit operation failures

integrations/ckprompt/smoke.go

@@ -27,7 +27,8 @@ type SmokeRequest struct {
 // without a builder, the seed is forwarded unchanged. Reports and errors from
 // PromptKit are both retained. A nil loader is kept as a suite wiring issue and
 // does not install a smoke-test callback. The callback also retains independent
-// engine diagnostics and terminal context with the report and error.
+// engine diagnostics and terminal context with the report and error. Native
+// operation errors supply terminal explanations when structured context is absent.
 func WithSmokeTesting[I, S any](
 	suite Suite[I, S],
 	load func(context.Context, ckconfig.Selection, I, S) (*promptkit.Engine, error),
@@ -65,6 +66,7 @@ func WithSmokeTesting[I, S any](
 		}
 
 		report, err := engine.SmokeTest(ctx, concreteRequest)
+		messages = messages.withOperationError(err)
 		return commandkit.Acquired[*promptkit.SmokeTestReport]{Value: report, Diagnostics: messages.diagnostics, Explanation: messages.explanation}, err
 	}
 	return suite