Add custom intervention modals

lib/create/isCustomMethodCardId.ts

@@ -0,0 +1,13 @@
+import type { CreateFlowState } from "../../app/(app)/create/types";
+
+/**
+ * User-authored method cards (UUID ids) register a meta row when finalized
+ * from {@link CustomMethodCardWizard}. Preset rows from `methods[]` never
+ * appear here — keeps edit surfaces from treating custom ids like presets.
+ */
+export function isCustomMethodCardId(
+  methodId: string,
+  customMeta: CreateFlowState["customMethodCardMetaById"],
+): boolean {
+  return Boolean(customMeta?.[methodId]);
+}