* WIP

* Add salt argument to instantiate call

* Fix lang compilation

* Fix salt to [u8; 4]

* Make create builder generic over Salt

* Use type state instead of ()

* Rename salt to salt_bytes

* Fmt

* Apply review suggestion: type state enum

* Apply review suggestion: separate impl block for salt_bytes getter

* Apply review suggestion: take salt bytes directly to avoid copy overhead

* Apply review suggestion: use Salt type state instead of leftover concrete type

* Apply review suggestion: fix doc tests