There aren't a lot of CardDAV Go libraries out there. Here's a start:
It needs some love though.
Is the plan for this ticket to add Carddav support to Aerc or itergrate with an existing tool.
Personally, I would like to have an integration with external tools to access the address book, either through CardDav or abook which stores the addresses locally.
I seem to be looking into old tickets, I am not sure if this is already resolved through some other means.
Here's a patch I sent a while back but haven't had a chance to circle back to, in case you are interested in picking it up: https://lists.sr.ht/~sircmpwn/aerc/%3C20190730191326.31038-1-ben%40benburwell.com%3E
Great. Will take a look into it when I have some time. Maybe I can work on the list view for completion as the mechanism is availble from your patch.