`runTrace` does not compose with other effects

Current function signature of `runTrace` is

```haskell
runTrace :: Eff '[Trace] a -> IO a
```

which is less composable than

```haskell
runTrace :: LastMember IO es => Eff (Trace ': es) a -> Eff es a
runTrace = interpret \case
  Trace s -> sendM $ putStrLn s
```

Do you think it'll be better to change it to that?