Better error message for reflection faliures due to missing reflection of constructors + refactor of core to logic

[AlecsFerra]

The error message was very unhelpful before (See #2457)

From

   Illegal type specification for `Fin.unFin`
    Fin.unFin :: forall n .
                 lq_tmp$db##0:(Fin.Fin n) -> {VV : GHC.Types.Int | VV == lqdc##$select##Fin.MkFin##1 lq_tmp$db##0
                                                                   && VV >= 0
                                                                   && VV < n}
    Sort Error in Refinement: {VV : int | VV == lqdc##$select##Fin.MkFin##1 lq_tmp$db##0
                                          && VV >= 0
                                          && VV < n}
    Unbound symbol lqdc##$select##Fin.MkFin##1 --- perhaps you meant: Fin.MkFin ?
    Just
   |
26 | unFin (MkFin i) = i
   | ^^^

To:

test/Testone2.hs:19:13: error:
    Uh oh.
    CallStack (from HasCallStack):
  panic, called at src/Language/Haskell/Liquid/Bare/Axiom.hs:355:26 in liquidhaskell-boot-0.9.10.1-inplace:Language.Haskell.Liquid.Bare.Axiom
    test/Testone2.hs:19:13 Cannot lift Haskell function `p2i` to logic
                           Cannot lift to logic the constructor `Fixme.P` consider enabling either --exactdc or --reflection
   |
19 | {-@ reflect p2i @-}
   |             ^

I think to make it even better we should either handle the panic gracefully (best solution) or at least remove all the call stack information since is rather unhelpful to the user

[facundominguez]

LGTM!