Send error from chatgpt.SendMessage, add tgbot package, conversations management by chatGPT

[dhilman]

Was initially planning on fixing sending of error from SendMessage only, but felt hesitant on growing the main function further so came the moving of things around.

Conversation management (i.e. mapping from chatID to conversationID and lastMessageID) felt heavily coupled to the chatgpt package, so have moved that there. This data (convoID & lastMessageID) is now not used in any other packages, so ChatResponse updated to only contain the Message.

A lot of logic in the main around sending a message through tgbotapi, similarly to other packages imo this deserved a thin wrapper package, exposing methods like: Send, SendAsLiveOutput.

[m1guelpf]

LGTM! If you could just resolve the merge conflicts (we've since made the message edit debounce timing configurable), I'll be happy to merge!

[dhilman]

thx @m1guelpf, all done, editInterval added to params of tgbot.New(...)

[m1guelpf]

Thank you for your contribution, @dhilman!