Consider switching the GIFs tooling

[Toreno96]

The current GIFs we have in the README were created using the macOS recording tool and converted using https://gifs.com/.

This is probably not the optimal solution, as the region has to be set manually (and as a result, it's not consistent between the recordings), and the converter leaves the watermark. And it takes a lot of time to do all of that.

We will definitely create new GIFs if we introduce the major changes to the interface, so we should research some better tooling.

We could consider using the tools recommended here (https://asciinema.org/ + https://github.com/marionebl/svg-term-cli).