Stop a channel (will stop all connected engines and rtsp-pull ingests)

Stops all connected engines and all connected rtsp-pull ingests of the channel. Running engines are stopped gracefully (playlists are closed so that viewers see the stream end, then the engine is torn down; stopping for typically 10–20 seconds). To skip the graceful shutdown use POST /channels/{id}/force-stop; engines that are already stopping are force stopped by this endpoint as well, so calling it twice also force stops the channel. Engines in error are always force stopped.