Disable Code Completion if Intero is not installed

[jpotecki]

If I am within a Stack project which doesn't has intero installed VS Code gets super slow. By default Haskelly should disable code completion if intero isn't installed + give a warning + Maybe (offer a button which runs stack install intero)

[glyn]

I notice that https://github.com/chrisdone/intero has been archived (and can't be installed with recent versions of GHC, without overriding the version checks). So the feature requested in the OP seems essential (unless Haskelly is being wound down too?).