feat(org-chart): support standalone React integration and update guides

packages/org-chart-react/src/index.ts

@@ -1,5 +1,5 @@
 "use client";
 
 export { OrgChart } from './OrgChart.js';
-export type { OrgChartProps } from './types.js';
+export type { OrgChartProps, OrgChartEmployeeSelection, OrgChartEmployeePopupProps } from './types.js';
 export type * from '@hm-design/org-chart';