More proper overloads with suspend handlers

[nerzhulart]

No description provided.

[Iliya-usov]

To be honest, I find this method a little strange

1. CoroutineContext often encompasses a dispatcher. passing coroutineContext + handlerScheduler looks contradictory.

2. I don't see any reason to pass outer scope here. This rd-call handler has his own scope/lifetime, which is cancelled when the counterpart scope/lifetime is cancelled, having two sopes looks also looks contradictory to me.

3. In your implementation we lose coroutine cancellation, because you don't use a lifetime received with the request to create the coroutine.

4. In this method we first go to the handlerScheduler (the protocol scheduler in most cases) and only after that we go to coroutineContext, in some cases this can be a problem if for example the main thread is stuck, but we don't really need the main thread at all, this can cause performance problems.

So I believe that we don't need that kind of API in the platform, because that API has a lot of non-obvious and contradictory moments, but at the same time it's easy to write that kind of code in your specific case.

I would prefer that kind of API:

fun <TReq, TRes> IRdEndpoint<TReq, TRes>.setSuspend(coroutineContext: CoroutineContext, handler: suspend CoroutineScope.(Lifetime, TReq) -> TRes) {
    val dispatcher = coroutineContext[ContinuationInterceptor] as? CoroutineDispatcher
    requireNotNull(dispatcher) { "coroutineContext: $coroutineContext doesn't have a CoroutineDispatcher" }
    
    val scheduler = dispatcher.asRdScheduler
    set(cancellationScheduler = SynchronousScheduler, scheduler) { lt, req ->
        lt.startAsync(coroutineContext, CoroutineStart.UNDISPATCHED) { handler(lt, req) }.toRdTask()
    }
}

Or we can use protocol dispatcher in case if coroutine context doesn't have corotineDispatcher

[Iliya-usov]

I don't see any reason do deprecate this method, and more over force people to pass CoroutineScope here