can't infer ConstructedAtomType properly

Hi, @agentm

I was creating a schema by trying project-m36-typed example with `CrashSafePersistence` db, and then tried to test an insert by tutd. But I can't find a way to input `ConstructedAtomType` in tutd. I can input `Just "something"` but not `Nothing`. It seems tutd can't infer Nothing's type.

```
TutorialD (master/main): :showexpr temp
┌───────────────────────────────────┬──────────────────────┬───────────────────────┐
│phoneNumberComment::Maybe (a::Text)│phoneNumberEmail::Text│phoneNumberNumber::Text│
├───────────────────────────────────┼──────────────────────┼───────────────────────┤
│Just "12345" │"12345" │"12345" │
└───────────────────────────────────┴──────────────────────┴───────────────────────┘
TutorialD (master/main): insert temp relation{tuple{ phoneNumberComment (Just "12346"), phoneNumberEmail "12346", phoneNumberNumber "12346"}}
TutorialD (master/main): :showexpr temp
┌───────────────────────────────────┬──────────────────────┬───────────────────────┐
│phoneNumberComment::Maybe (a::Text)│phoneNumberEmail::Text│phoneNumberNumber::Text│
├───────────────────────────────────┼──────────────────────┼───────────────────────┤
│Just "12345" │"12345" │"12345" │
│Just "12346" │"12346" │"12346" │
└───────────────────────────────────┴──────────────────────┴───────────────────────┘
TutorialD (master/main): insert temp relation{tuple{ phoneNumberComment (Nothing), phoneNumberEmail "12346", phoneNumberNumber "12346"}}
ERR: TypeConstructorTypeVarsMismatch (fromList ["a"]) (fromList [])

```

And in the meantime, I can't auto-derive some newtype Atomable from base Atoms.

```
newtype SafeId = SafeId B.ByteString
deriving (Eq, Ord, Show, Generic)
deriving newtype (NFData, Binary)

-- * Couldn't match representation of type `proxy ByteString'
-- with that of `proxy SafeId'
-- arising from the coercion of the method `toAtomType'
-- from type `forall (proxy :: * -> *).
-- proxy ByteString -> ProjectM36.Base.AtomType'
-- to type `forall (proxy :: * -> *).
-- proxy SafeId -> ProjectM36.Base.AtomType'
-- NB: We cannot know what roles the parameters to `proxy' have;
-- we must assume that the role is nominal
-- * When deriving the instance for (Atomable SafeId)

```
It's due to some type role issue. And change `proxy` to `Proxy` may work (saw this advice somewhere).
Is there any reason to have a `toAtomType :: proxy a ->` ... with a type variable instead of the Proxy type?