This works for me (for React, I think it should also work for Vue):

import { defineConfig } from 'vite' // 2.8.0
import react from '@vitejs/plugin-react' // 1.0.7

export default defineConfig ({
  plugins: [react()],
  build: {
    rollupOptions: {
      output: {
        manualChunks: {}
      },
    },
  },
})