Harden server draft sync (Save & Exit + post-login transfer)

lib/create/draftHydrationUtils.ts

@@ -0,0 +1,6 @@
+import type { CreateFlowState } from "../../app/create/types";
+
+/** True when the client should treat a draft payload as non-empty for hydration / conflict checks. */
+export function createFlowStateHasKeys(state: CreateFlowState): boolean {
+  return Object.keys(state).length > 0;
+}