feat: authsession service

authsession/internal/ports/errors.go

@@ -0,0 +1,16 @@
+// Package ports defines the storage-agnostic and transport-agnostic service
+// boundaries used by the auth/session application layer.
+package ports
+
+import "errors"
+
+var (
+	// ErrNotFound reports that a requested source-of-truth record or remote
+	// subject does not exist in the dependency behind the port.
+	ErrNotFound = errors.New("ports: record not found")
+
+	// ErrConflict reports that a create or compare-and-swap style mutation
+	// cannot be applied because the current dependency state no longer matches
+	// the caller expectation.
+	ErrConflict = errors.New("ports: conflict")
+)