[playground] Decouple playground from compiler

Currently the playground is setup as a linked workspace for the
compiler which complicates our yarn workspace setup and means that snap
can sometimes pull in a different version of react than was otherwise
specified.

There's no real reason to have these workspaces combined so let's split
them up.

ghstack-source-id: 56ab064b2fc45366f5d96d37c5d4c5dc26590234
Pull Request resolved: https://github.com/facebook/react/pull/31081