Implement GroupV2 links
Format is https://signal.group/#[bunch-of-zooi] Also signl://signal.group/#[bunch-of-zooi]
libcontentaction
is implementing support for domain-based context links: https://git.sailfishos.org/mer-core/libcontentaction/merge_requests/18
Our captcha3
branch has some work on DBus based message reception, which, in this case, should work fine (since these are actually valid URLs!)