feat: production build with vite

[antfu]

This PR introduces the ability to run nuxt build use Vite, resolve #167. close #7

This also made Nuxt 2 working with vite plugins, tested with https://github.com/antfu/vitesse-nuxt/tree/play/vite-build

The build is disable by default, and can be enabled with:

// nuxt.config
export default {
  buildModules: [
    'nuxt-vite'
  ],
  vite: {
    build: true
  }
}

Ideally we would like to make it default to true, but do we want to release is as opt-in experimental feature and change it in the future (or we have it default to true and releases with beta dist?) /cc @pi0 @atinux WDYT?

This should be released as a minor change.

[codecov-commenter]

Codecov Report

Merging #179 (d3070c6) into main (f0044db) will decrease coverage by 13.71%.
The diff coverage is 52.32%.

@@             Coverage Diff             @@
##             main     #179       +/-   ##
===========================================
- Coverage   90.16%   76.44%   -13.72%     
===========================================
  Files          11       11               
  Lines         183      242       +59     
  Branches       43       53       +10     
===========================================
+ Hits          165      185       +20     
- Misses         18       57       +39     

Impacted Files	Coverage Δ
test/fixture/nuxt.config.js	100.00% <ø> (ø)
src/client.ts	91.30% <33.33%> (-8.70%)	⬇️
src/server.ts	56.84% <48.00%> (-33.41%)	⬇️
src/index.ts	73.17% <100.00%> (+0.67%)	⬆️
src/utils/wpfs.ts	100.00% <100.00%> (ø)
src/vite.ts	95.45% <100.00%> (+0.21%)	⬆️

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[antfu]

For testing, do you think we should introduce cypress for e2e test?

[pi0]

It seems we have a hydration error with fixture production build: (still reproducable but checking later)

[antfu]

@pi0 Should we make it default to true and for users to opt-out? Or maybe in next breaking?

[pi0]

I vote for next major (0.3.x) so that we can fix leftover issues like modern mode mapping, speeding up and better legacy.