Define processing outcomes and failure contracts

internal/framework/structuredoutput/failure.go

@@ -1,6 +1,10 @@
 package structuredoutput
 
-import "errors"
+import (
+	"errors"
+
+	"gitea.maximumdirect.net/eric/audita/internal/framework/outcomes"
+)
 
 // FailureKind separates invalid generated content from operational failures.
 type FailureKind string
@@ -13,14 +17,31 @@ const (
 // Failure exposes a safe message while retaining the typed cause for callers.
 // The cause must not be serialized or formatted directly in user artifacts.
 type Failure struct {
-	Kind    FailureKind
+	Kind    FailureKind // Retained until the adapter switches to reason-based classification.
+	Class   FailureClass
+	Reason  outcomes.ReasonCode
 	Message string
 	Cause   error
 }
 
+// FailureClass determines whether domain processing may safely skip a model
+// operation or must stop the run. Parent cancellation always stops the run.
+type FailureClass string
+
+const (
+	FailureRecoverable FailureClass = "recoverable"
+	FailureFatal       FailureClass = "fatal"
+	FailureCanceled    FailureClass = "canceled"
+)
+
 func (f *Failure) Error() string { return f.Message }
 func (f *Failure) Unwrap() error { return f.Cause }
 
+func IsRecoverable(err error) bool {
+	var failure *Failure
+	return errors.As(err, &failure) && failure.Class == FailureRecoverable
+}
+
 func IsMalformedError(err error) bool {
 	var failure *Failure
 	return errors.As(err, &failure) && failure.Kind == FailureMalformedOutput