chore(ckeditor5): integrate building of ballon & decoupled

packages/ckeditor5/src/index.ts

@@ -1 +1,9 @@
-export * from './lib/ckeditor5.js';
+import { EditorWatchdog } from "ckeditor5";
+import BalloonEditor from "./ckeditor_balloon.js";
+import DecoupledEditor from "./ckeditor_decoupled.js";
+
+export default {
+	BalloonEditor,
+	DecoupledEditor,
+	EditorWatchdog
+}