We currently send NickServ identify message after RPL_WELCOME and join message after RPL_ENDOFMOTD. RPL_ENDOFMOTD is sent after RPL_WELCOME, but sometimes NickServ takes longer and authentication isn't successful until after RPL_ENDOFMOTD. When that happens we end up sending JOIN message before authenticating, which fails for channels with +R (login-to-join).

When nickserv_ident is used we should wait to hear from NickServ before sending JOIN.

Implementation is simple: just check for PRIVMSGs from NickServ in update in libtiny_client/src/state.rs and send join messages there. We'll need a bool field for whether we've sent JOIN already as we don't want to send JOIN every time we get a PRIVMSG from NickServ. The state should be false initially and reset on disconnect, and should be true after sending the JOIN message.