Add prepare script

package.json

@@ -3,6 +3,7 @@
   "scripts": {
     "docs": "npm run build && npm exec documentation build qunit-dom/dist/qunit-dom.js --config documentation.yml -f md -o API.md",
     "build": "cd qunit-dom && npm run build",
+    "prepare": "pnpm build",
     "release": "cd qunit-dom && npm run release",
     "lint": "pnpm --filter '*' lint",
     "lint:fix": "pnpm --filter '*' lint:fix",