ui: external module support

packages/ui-default/utils/loadModule.ts

@@ -0,0 +1,10 @@
+export default async function loadExternalModule(target: string) {
+  const ele = document.createElement('script');
+  ele.src = target;
+  await new Promise((resolve, reject) => {
+    ele.onload = resolve;
+    ele.onerror = reject;
+    document.head.appendChild(ele);
+  });
+  return window.exports;
+}