I’m facing a file extension error for a Vue3 app on Heroku

The build is complete but then i get this error :

TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension “.vue” for /app/src/App.vue
at Object.getFileProtocolModuleFormat [as file:] (node:internal/modules/esm/get_format:160:9)
at defaultGetFormat (node:internal/modules/esm/get_format:203:36)
at defaultLoad (node:internal/modules/esm/load:143:22)
at async ModuleLoader.load (node:internal/modules/esm/loader:396:7)
at async ModuleLoader.moduleProvider (node:internal/modules/esm/loader:278:45) {
code: ‘ERR_UNKNOWN_FILE_EXTENSION’

main.js :

import { createApp } from 'vue'
import App from './App.vue'

createApp(App).mount('#app')

package.json

{
  "name": "myApp",
  "type": "module",
  "version": "0.1.0",
  "private": true,
  "scripts": {
    "serve": "vue-cli-service serve",
    "build": "vue-cli-service build",
    "lint": "vue-cli-service lint",
    "start": "node src/main.js"
  },
  "dependencies": {
    "core-js": "^3.6.5",
    "vue": "^3.0.0"
  },
  "devDependencies": {
    "@vue/cli-plugin-babel": "~4.5.15",
    "@vue/cli-plugin-eslint": "~4.5.15",
    "@vue/cli-service": "~4.5.15",
    "@vue/compiler-sfc": "^3.0.0",
    "babel-eslint": "^10.1.0",
    "eslint": "^6.7.2",
    "eslint-plugin-vue": "^7.0.0"
  },
  "eslintConfig": {
    "root": true,
    "env": {
      "node": true
    },
    "extends": [
      "plugin:vue/vue3-essential",
      "eslint:recommended"
    ],
    "parserOptions": {
      "parser": "babel-eslint"
    },
    "rules": {}
  },
  "browserslist": [
    "> 1%",
    "last 2 versions",
    "not dead"
  ]
}

Procfile

web:node src/main.js