[1245] Where is the "Entry point" like app.js in the Vuejs?

I try to put something in common. but only solution i found here is put it on header or footer.

Right now i try to use Vue-analytic

import Vue from 'vue'
import VueAnalytics from 'vue-analytics'

Vue.use(VueAnalytics, {
  id: 'UA-XXX-X'
})

so im not sure where to write

Vue.use(VueAnalytics, {
  id: 'UA-XXX-X'
})

thank you