Finalize stack integration

Since https://github.com/commercialhaskell/stack/pull/5585 was merged by @mpilgrem, we should do two things:

1. enable stack installation by default when running the bootstrap script
2. install (if the user wants) a stack GHC installation hook that uses ghcup for GHC installation
   • this fixes ABI issues with stack and HLS
   • question: should this only be done in the bootstrap script? Or embedded into the ghcup binary?

changed milestone to %0.1.18.0

added scopestack typeimprovement labels

mentioned in issue #387 (closed)

This will require an actual release with the new hooks.

removed milestone %0.1.18.0

Stack 2.9.1, with the hook, has now been released.

marked the checklist item enable stack installation by default when running the bootstrap script as completed

marked the checklist item install (if the user wants) a stack GHC installation hook that uses ghcup for GHC installation as completed

Done !285 (merged)

closed