Support ircv3 features

[jhthorsen]

Would be nice if Convos could support some/all of the features listed on https://ircv3.net/irc/. I'm not jumping on this issue though, since libera.chat (my main network) does not support too many features: https://ircv3.net/support/networks#networks-1 There are some test networks though, that I might use to see what to implement.

Probably need to make some new tasks to cover the different features:

• [x] Capability Negotiation: CAP, CAP 302, cap-notify
• [x] WebIRC: WEBIRC - #546
• [ ] Echo Message: echo-message
• [ ] Message IDs: message-ids, msgid
• [ ] Monitor: monitor
• [ ] Labeled Responses: labeled-response
• [ ] Away Notifications: away-notify - #360
• [ ] Message Tags
• [ ] Userhosts in NAMES: userhost-in-names
• [ ] Setname: setname
• [ ] Client-Only Tags: react, reply, typing
• [ ] Multiple Prefixes: multi-prefix
• [x] SASL Authentication: SASL v3.1, SASL v3.2, SNI #356, STS
• [ ] Invite Notify: invite-notify
• [ ] Account Tracking: account-notify, account-tag, extended-join
• [ ] Changing Usernames and Hostnames: chghost
• [ ] Server Time: server-time
• [ ] Batches: batch

[poVoq]

With IRCv3 being adopted more and more, it would be nice if Convos added more IRCv3 support.

Right now it is now even listed on the IRCv3 clients table, see: https://github.com/ircv3/ircv3.github.io/issues/481

[jhthorsen]

My time has gotten way more limited, so I'm not sure when I'll be able to work on this, but I wonder what people would be interested in. "Echo Message" is the only one I'm partially interested in, but it will also just add more code for the same feature, so... Maybe not that interested.

Maybe I could add one comment per feature and let people add thumbs up? I don't expect too many thumbs up though 🙈