feat(org-chart): add core cards and fixed-layout integration

packages/org-chart/src/data/snapshot.ts

@@ -0,0 +1,14 @@
+/** Own a JSON-like input at the call boundary; never retain consumer objects. */
+export function snapshotOrgChartDataset<T>(input: T): T {
+  const copy = structuredClone(input);
+  const pending: unknown[] = [copy];
+  const seen = new WeakSet<object>();
+  while (pending.length) {
+    const current = pending.pop();
+    if (current === null || typeof current !== 'object' || seen.has(current)) continue;
+    seen.add(current);
+    for (const child of Object.values(current)) pending.push(child);
+    Object.freeze(current);
+  }
+  return copy;
+}