fix(subflow-node-origin): use node origin in node position calculation

examples/vite-app/src/examples/Subflow/index.tsx

@@ -11,6 +11,7 @@ import ReactFlow, {
   Controls,
   MiniMap,
   Background,
+  NodeOrigin,
 } from 'reactflow';
 
 import DebugNode from './DebugNode';
@@ -21,6 +22,7 @@ const onNodeClick = (_: MouseEvent, node: Node) => console.log('click', node);
 const onEdgeClick = (_: MouseEvent, edge: Edge) => console.log('click', edge);
 
 const defaultViewport = { x: 0, y: 0, zoom: 1.5 };
+const nodeOrigin: NodeOrigin = [0.5, 0.5];
 
 const initialNodes: Node[] = [
   {
@@ -90,7 +92,7 @@ const initialNodes: Node[] = [
   {
     id: '5a',
     data: { label: 'Node 5a' },
-    position: { x: 25, y: 50 },
+    position: { x: 0, y: 0 },
     className: 'light',
     parentNode: '5',
     extent: 'parent',
@@ -205,6 +207,7 @@ const Subflow = () => {
       onlyRenderVisibleElements={false}
       nodeTypes={nodeTypes}
       fitView
+      nodeOrigin={nodeOrigin}
     >
       <MiniMap />
       <Controls />