Otherwise the emitted type definitions may break downstream users who do
not have these options enabled.

Thanks @meteorlxy for spotting this issue.

- new `<script setup>` vuejs/rfcs#227
- new `<style>` variable injection vuejs/rfcs#231

Requires a version of `@vue/compiler-sfc` that supports the above features.

Also should fix vuejs#1723

…uejs#1764)

This option provides a solution for vuejs#1734

When testing with mocha + mochapack, even though the target
environment is `node`, the compiled component is expected to be run
with `jsdom` rather than with a Node.js server, so it should still be
a client bundle.

This fixes the css var injection having different id from generated CSS