Pre-release should be 0.0.1.

package.json

 {
   "name": "@ckeditor/ckeditor5-build-decoupled-document",
-  "version": "1.0.0-alpha.2",
+  "version": "0.0.1",
   "description": "CKEditor 5 document editor build.",
   "keywords": [
     "ckeditor5",