[Vuejs]-After running build on my quasar vuejs app: >app:build Built files are meant to be served over an HTTP server

You can host your app on firebase hosting.
Go to https://console.firebase.google.com , and create a project.
Download the firebase-tools and deploy your built files there.
Additionally, you can also use the cloud messaging from firestore in your app.
For localhost, you can use “serve” module.