remove non-maintained MINERVA project

[haraldsteinlechner]

There is a lot of deprecated code in the repository we need to get rid of (current half-working state does not work when updating to dotnet8 etc). I propose to delete those code paths completely and get it back if needed at some point (a lot of effort to make it work anyways)

[haraldsteinlechner]

@RebeccaNowak There is a lot of code referencing minerva datatypes in for example linking. Is it safe to remove those?
e.g.

type Action =
  | Camera           of FreeFlyController.Message
  | KeyUp            of key : Keys
  | KeyDown          of key : Keys  
  | UpdateDockConfig of DockConfig    
  | PickingAction    of PickingAction
  | LinkingAction    of LinkingAction
  | MinervaAction    of MinervaAction
  | PickPoint        of V3d

[RebeccaNowak]

I wasn't involved in Minerva, but I think we can remove them since Minerva isn't being used anymore