Use notmuch's python bindings

[agenbite]

While investigating how to change the separator of the authors list in the search view (which is | [bar+space] and should be , [comma+space] or something similar), I noticed that Dodo makes calls to notmuch through subprocess.

Wouldn't it be better to use notmuch's python bindings instead of calls to subprocess.run?

[akissinger]

When I experimented with python bindings about a year ago, I found them somewhat troublesome to set up, particularly if you want the latest ("notmuch2") bindings, it seems you need to build notmuch from the git repo.

I haven't seen a particularly good use-case for the python bindings yet, especially since notmuch already produces JSON which is pretty easy to handle from python. It might be worth looking into this again if we want to do some fancier stuff like displaying search results incrementally.