message: refactor(elements): cast source and target of edge to string
diff: @@ -82,6 +82,8 @@ export const parseElement = (element: Node | Edge): Node | Edge => {
  if (isEdge(element)) {
  return {
  ...element,
  + source: element.source.toString(),
  + target: element.target.toString(),
  id: element.id.toString(),
  type: element.type || 'default',
  };
  