refactoring for standalone turbopack cli and benchmarking in turbo (#4553)
### Description
* enable bench CI again
* add @vercel/turbopack-node alias to avoid duplicate IPC logic add
turbopack-bench to share benchmarking logic
* add next.js --turbo to benchmark
* add turbopack-cli as standalone dev server
* move shared dev runtime code to turbopack-dev
* move .env loading to turbopack-env
fixes WEB-473
fixes WEB-429
fixes WEB-893
next.js: https://github.com/vercel/next.js/pull/48307