Issue a warning if the stream direction and type are incompatible
In PipeWire, an input stream is always a stream that is receiving data, and an output stream is always one that is sending data. Therefore, a source will generally be an output stream, and a sink will generally be an input stream.
Mixing these up leads to hard-to-debug problems. PipeWire should clearly document this, and should issue a warning if an input stream is a source, or if an output stream is a sink.
Edited by Demi Marie Obenour