Add a ZIO-style Service type for idiomaticity points

[kitlangton]

There's usually (when adhering to the ZIO module pattern) a Service trait which defines interface (send and openWebsocket here).
In lieu of that refactoring, it could be nice to expose a Service type alias such that it could be idiomatically accessed when relying upon SttpClient in ones own ZLayers.

Then it would be trivial to refactor from

  def live(token: String): ZLayer[Console with SttpClient, Nothing, SlackClient] =
    ZLayer
      .fromServices[Console.Service, SttpBackend[Task, Stream[Throwable, Byte], WebSocketHandler], SlackClient.Service](
        (console: Console.Service, sttp: SttpBackend[Task, Stream[Throwable, Byte], WebSocketHandler]) =>
          LiveSlackClient(console, sttp, token)
      )

to

  def live(token: String): ZLayer[Console with SttpClient, Nothing, SlackClient] =
    ZLayer
      .fromServices[Console.Service, SttpClient.Service, SlackClient.Service](
        (console: Console.Service, sttp: SttpClient.Service) =>
          LiveSlackClient(console, sttp, token)
      )

Ahh, much better ;)

I'd also be happy to fully refactor this to use the trait Service pattern if that's something you'd be into, my dear sttp-eople.

Take care and thx for all the lovely software!

[adamw]

Released in 2.2.5, thanks!

[kitlangton]

Oh! Thank you @adamw :)