Webui: Delete conversation branches

[a-e-k]

Right now, the Webui has:

[Copy] [Edit message] [<] X/N [>]

on user turns, and:

[<] X/N [>] [Regenerate response] [Copy]

on model turns.

It's great to be able to go back and tweak messages, regenerate responses, and generally generate lots of branches in the dialogue. However, many of these can be dead-ends: incorrect responses, interrupted responses, etc. This chaff makes it harder to find the good branches.

I'd love to have a [Delete] or [Delete branch] button to let me prune the dead ends and responses I didn't like.

[a-e-k]

Closing. Thanks @allozaur, @ServeurpersoCom, and everyone else for the spiffy new webui which happens to have this..