This PR makes the global install more prominent. This is important for
non-JS workspaces since they may not have node or npm available. The
installation flow should be:
1. Install Nx (e.g. `brew install nx`)
2. Run `nx init` in your project
The `create-nx-workspace` is removed since it's already mentioned on the
intro page, and it is covered in tutorials. It is also not technically
an "install" command.
Preview:
https://nx-dev-git-docs-update-installation-nrwl.vercel.app/getting-started/installation
**Note:** The cross-platform NPM install is still featured first because
it'll work for everyone. It shouldn't be a concern for non-JS devs since
other tools like Claude Code also has `npm install --global` as their
install step.
Now that Nx is merged into
[`homebrew-core`](https://github.com/Homebrew/homebrew-core/pull/225452)
we no longer need to tap to access a non-official formula.
This PR updates our brew install to remove `brew tap nrwl/nx`. It also
mentions Linux for Homebrew since it is supported across different Linux
distros.
