Include frequency and buffering selector

Hi Rui, I know you're on vacation.
What I'm saying here isn't urgent, or even essential (but I do think it would be useful).
Read it whenever you want, enjoying your break comes first.
Thanks.
...

I finally realized that my suspicions about PipeWire were based on flawed assumptions.
Also, while technically it is more inaccurate than Jack, in practice its performance and resource management are better. And we keep adding, greater versatility and ease of management.

So now Qpwgraph is my tool to manage connections.
The only thing I miss is the typical frequency and buffer selector. Currently I have to resort to an external utility for this. This is it: https://github.com/cyber-sushi/pipewire-sample-rate-config

I found it here where it talks about commands to manage PipeWire:
https://linuxmusicians.com/viewtopic.php?t=25768

Considering that Qpwgraph is a specialized tool for PipeWire, it would make sense to be able to modify PipeWire's frequency/buffer values ​​from Qpwgraph.
I think that its place should be a new toolbar, so that we can customize the position of the selector.

I leave it to your consideration, if you see sense in it.

Enjoy your holidays :)