Layout transforms

Trees can be transformed in place (or structurally) before rendering:

import {
  transposeTree,
  horizontalMirrorInPlace,
  verticalMirrorInPlace,
  normalizeExtentsInPlace,
} from "@json-table/core";

• transposeTree(tree) — reflect over the main diagonal (rows become columns). Returns a new tree.
• horizontalMirrorInPlace(tree) — reverse column order.
• verticalMirrorInPlace(tree) — reverse row order.
• normalizeExtentsInPlace(tree) — recompute container extents bottom-up. Useful after manual tree surgery.