Delete, Clean and Repair .fsk folder automatically

[schuelet]

The .fsk folder for automatically installed R packages is still a major source of problems, even for experienced users.

• it remains a source of conflicts if it is referenced in .RProfile (.libPaths() )

  • on pressing the button "apply" or "close & apply" in KNIME preferences

• it needs to be removed if the user switches from the packaged R in FSK-Lab

• if user uses their own R, I propose not to use the .fsk folder at all (nor touch .RProfile at all)

  • maybe this has already been done but sometimes the reference to .fsk still remains in .RProfile

• this would only affect target 4.5.x and above, since on KNIME Server, we will phase out "traditional" R in favor of Conda R environments

• maybe, we also introduce some sort of auto-repair function, where the .fsk folder is completely removed if an R package cannot be loaded

  • in that case, afterwards we would start the automatic installation of CRAN packages again

• can we avoid to mess with .Rprofile at all, like we don't touch .Rprofile and only add the .fsk path to .libPaths during model execution?