chore: flatten src/ to root

utils/lazySchema.ts

@@ -0,0 +1,8 @@
+/**
+ * Returns a memoized factory function that constructs the value on first call.
+ * Used to defer Zod schema construction from module init time to first access.
+ */
+export function lazySchema<T>(factory: () => T): () => T {
+  let cached: T | undefined
+  return () => (cached ??= factory())
+}