wip: add pseudo speaker diarization pipeline based on segmentation stitching

[hbredin]

As segmentation models are getting better, it might make sense to revisit the idea of stitching based on segmentation alone. That's what this (WIP) pipeline does.

Also, that was an excuse for me to start experimenting with diart and ... I'm enjoying it so far :)

[juanmc2005]

very very cool, I think it also makes more sense with the powerset model because of the bigger window too. Let me know if you need a hand with this! We should also find a more catchy name for pseudo speaker diarization 😃