rix::rix(): R --vanilla -> R for shellHook to enable .Rprofile inheritance from rix_init()

[philipp-baumann]

No description provided.

[b-rodrigues]

I wonder if we should have a default shell_hook at all

[philipp-baumann]

I wonder if we should have a default shell_hook at all

true :-) maybe people call Rscript or any other stuff directly if they already use R. In with_nix() we also launch via Rscript and that does not need a shell hook

[philipp-baumann]

Will do a separate PR for this and also with the tests explicitly telling.