fix: missing prebuild script

Author: zcstarr

packages/example-site/package.json

@@ -5,6 +5,7 @@
   "scripts": {
     "docusaurus": "docusaurus",
     "start": "docusaurus start",
+    "prebuild": "bun run --cwd ../docusaurus-plugin build",
     "build": "docusaurus build",
     "swizzle": "docusaurus swizzle",
     "deploy": "docusaurus deploy",