message: launchpad-ledger: Add demo-node script to package.json
diff: "postbuild": "yarn move-types && yarn format-types",
  "build-or-skip": "[ -n \"$SKIP_BUILD\" ] || yarn build",
  "test": "echo 'Please check README for information on how to manually run the demo'",
  + "demo-node": "yarn build-or-skip && node ./demo/node.js",
  "coverage": "nyc --reporter=text --reporter=lcov yarn test --quiet",
  "pack-web": "yarn build-or-skip && webpack --mode development --config webpack.demo.config.js"
  },
  