A streamed response containing a response header and a streamable body.

Note that this is only usable with a stream call, i.e.

import scala.concurrent.{ ExecutionContext, Future }

import org.apache.pekko.util.ByteString
import org.apache.pekko.stream.scaladsl.Source

import play.api.libs.ws.DefaultBodyReadables._
import play.api.libs.ws.ahc.StandaloneAhcWSClient

class MyClass(ws: StandaloneAhcWSClient) {
  def doIt(implicit ec: ExecutionContext): Future[String] =
    ws.url("http://example.com").stream().map { response =>
       val _ = response.body[Source[ByteString, _]]
       ??? // process source to String
    }
}