feat(xanthous): Add a method to get the name for a type of entity

I didn't end up using this directly for the thing I was doing, but it
still seems generally useful enough that I'm keeping it around for now

Change-Id: I05c8902d75845f2230ec2373a9677d61cfaafafd
Reviewed-on: https://cl.tvl.fyi/c/depot/+/3206
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI

users/grfn/xanthous/src/Xanthous/Game/State.hs

@@ -56,6 +56,8 @@ module Xanthous.Game.State
   , downcastEntity
   , _SomeEntity
   , entityIs
+  , entityTypeName
+
     -- ** Vias
   , Color(..)
   , DrawNothing(..)
@@ -394,6 +396,10 @@ entityIs = isJust . downcastEntity @a
 _SomeEntity :: forall a. (Entity a, Typeable a) => Prism' SomeEntity a
 _SomeEntity = prism' SomeEntity downcastEntity
 
+-- | Get the name of the type of 'SomeEntity' as a string
+entityTypeName :: SomeEntity -> Text
+entityTypeName (SomeEntity e) = pack . tyConName . typeRepTyCon $ typeOf e
+
 newtype DeriveEntity
   (blocksVision :: Bool)
   (description :: Symbol)