Add missing script

Author: febo

clients/legacy/package.json

@@ -11,7 +11,8 @@
     "lint": "eslint --ext js,ts,tsx src",
     "lint:fix": "eslint --fix --ext js,ts,tsx src",
     "format": "prettier --check src test",
-    "format:fix": "prettier --write src test"
+    "format:fix": "prettier --write src test",
+    "prepublishOnly": "pnpm build"
   },
   "files": [
     "/dist/src"