QGB e2e use signaling channel to notify

[rach-id]

Currently, the QGB is using context extensively to communicate. This can be improved via the use of a signaling channel.
This PR is an example of how to do it: #512 in here:

celestia-app/x/qgb/orchestrator/orchestrator_command.go

Lines 77 to 86 in 7169d9a

	func trapSignal(logger tmlog.Logger, cancel context.CancelFunc) {
	var sigCh = make(chan os.Signal, 1)
	signal.Notify(sigCh, syscall.SIGTERM)
	signal.Notify(sigCh, syscall.SIGINT)
	sig := <-sigCh
	logger.Info("caught signal; shutting down...", "signal", sig.String())
	cancel()
	}

[evan-forbes]

Currently, the QGB is using context extensively to communicate.

mind elaborating on this a bit? is this referencing our reliance on ctx.Done()?

[rach-id]

Yes, exactly. We have multiple functions waiting for a signal to stop processing. Currently, we're forced to use context timeouts and cancells in a complex way to notify all threads. However, we can use an easier mechanism using a special notify channel that can be used to trap any error or exit signal and notify everything to stop.