All options of the `Config` do not affect the `Channel`

[adithyaov]

The stopping condition of the stream is baked into concatMapWithChanKGeneric depending on the Config. If one simply creates a Channel with StopAny and sends streams to it, things won't work as expected. This can be rather confusing. Is it possible to make _stopWhen in the Config a function? A stream modifier that changes the stop continuation accordingly.