{
  "name": "webpack-app",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "scripts": {
    "start": "webpack --mode production --watch",
    "dev": "webpack --mode development",
    "serv": "static -H \"{\"Cache-Control\": \"no-cache, must-revalidate\"}\"" 
  },
  "devDependencies": {
    "html-webpack-plugin": "^3.2.0",
    "node-static": "^0.7.11",
    "webpack": "^4.39.2",
    "webpack-cli": "^3.3.6"
  }
}
в дальнейшем рекомендую использовать редактор типа 
этого