ooni/probe: pass richer input object to experiments

[bassosimone]

This issue is a child of #1291. The general idea is that we would like to remove the internal barriers inside ooni/probe-cli implementation that prevent us from obtaining from the backend and using a richer input model. We can consider this issue closed when the probe knows about obtaining richer input from the backend, can obtain and use it for specific experiments (e.g., urlgetter, stunreachability) that already have richer input needs that we cannot currently take advantage of, and we have released this code in production.

[bassosimone]

As explained in ooni/2023-05-richer-input@7871d3b, the https://github.com/ooni/2023-05-richer-input contains a prototype that explores the richer input domain and redesigns ooniprobe around richer input.

[bassosimone]

This used to be an Epic and was quite broad. I created more fine grained issues and I am going to close this one.