Static compression

[aleclarson]

Is your feature request related to a problem? Please describe.
Provide built-in support for "static compression", which means compressing static assets at build-time.

Describe the solution you'd like
Maybe a compress flag in vite.config.js that uses brotli?

Describe alternatives you've considered
Figure out how to get rollup-plugin-brotli working either in vite.config.js (via rollupInputOptions.plugins) or through a custom Vite plugin.

[brmdbr]

This would be very welcome! rollup-plugin-brotli doesn't work out of the box with Vite.

[underfin]

Same with #880. This happend because the vite use bundle.generate, so the writebundle of plugins won't invoke.Just track it for #880