settle on a broader naming convention for supported containers

the ghci stuff may feel a bit dated now... and the SNL containers are pretty general (they can run anywhere!)

cc @bartgol

Review the repository's existing container recipes and naming, paying particular attention to the ghci and SNL containers mentioned in the issue. Compare their current names and intended scope, then use the issue discussion to establish whether a broader convention has been agreed. Done means the convention and affected names are clearly settled.

Written by the indexing model from the issue text.