fix: Export CK5 Wiris classes (#1084)

Author: carla-at-wiris

packages/ckeditor5/src/index.js

@@ -1,3 +1,6 @@
 import MathType from "./plugin.js";
+import CKEditor5Integration from "./integration.js";
+import { MathTypeCommand, ChemTypeCommand } from "./commands.js";
 
 export default MathType;
+export { CKEditor5Integration, MathTypeCommand, ChemTypeCommand };