The Bun build issue was caused by Turborepo passing through
`USERPROFILE` from the env. Probably need to file a bug with Bun:
```
Works:
env: USERPROFILE: undefined
CWD: `D:\a\tailwindcss\tailwindcss\packages\@tailwindcss-standalone`
Fails:
env: USERPROFILE: "C:\Users\runneradmin"
CWD: `D:\a\tailwindcss\tailwindcss\packages\@tailwindcss-standalone`
```