Refactor chatbot: Integrating LLM responses in the chabot tab

[amannaik247]

This is a draft implementation to integrate routing of input from the user to the aiml engine(existing) or LLM response based on weather the question is pattern based or complex.
If it returns False then it is routed to the get_llm_response function.
This code successfully integrates LLM response to the chatbot voice and the chat logs. As well as logs the response on the terminal.
It also temporarily saves conversation text for context into further responses.
(This is to verify the code I showed in my GSoC proposal)