Quantify over the scope type variable (s) last

[Icelandjack]

When you finalize the library, consider quantifying over the scope type variable s last now that the order matters

newKey :: forall a s. KeyM s (Key s a)
newKey = KeyM $ \s -> Key (supplyName s)

This lets us write

-- CURRENT: newKey @_ @Int :: forall k (t :: k). KeyM t (Key t Int)

newKey @Int :: forall k (t :: k). KeyM t (Key t Int)