Use LabelOptic and add LeanAppState

Wrt #186

lib/GHCup/Types.hs

@@ -1,9 +1,12 @@
 {-# OPTIONS_GHC -Wno-orphans #-}
 {-# LANGUAGE CPP               #-}
 {-# LANGUAGE BangPatterns      #-}
+{-# LANGUAGE DataKinds         #-}
 {-# LANGUAGE DeriveGeneric     #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE FlexibleContexts  #-}
 {-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE DuplicateRecordFields #-}
 
 {-|
 Module      : GHCup.Types
@@ -346,8 +349,14 @@ data AppState = AppState
   { settings :: Settings
   , dirs :: Dirs
   , keyBindings :: KeyBindings
-  , ghcupInfo :: ~GHCupInfo
-  , pfreq :: ~PlatformRequest
+  , ghcupInfo :: GHCupInfo
+  , pfreq :: PlatformRequest
+  } deriving (Show, GHC.Generic)
+
+data LeanAppState = LeanAppState
+  { settings :: Settings
+  , dirs :: Dirs
+  , keyBindings :: KeyBindings
   } deriving (Show, GHC.Generic)
 
 instance NFData AppState
@@ -507,4 +516,3 @@ instance (Monad m, Alternative m) => Alternative (LoggingT m) where
 instance MonadLogger m => MonadLogger (Excepts e m) where
   monadLoggerLog a b c d = Trans.lift $ monadLoggerLog a b c d
 
-