TTG: Move HsModule to L.H.S
Progress towards #21592
When complete, should separate Ghc-specific and independent bits in HsModule, and have HsModule in the client-independent Language.Haskell.Syntax module, and the same with ImpExp.
Basically LH.Syntax and LHS.ImpExp are populated and things are worked with the TTG idea
Edited by Rodrigo Mesquita