The current implementation needs changes to work properly with the RAG service and changes to pass the functional, kernel, and unit tests.

Problem/Motivation

The current implementation needed some changes to work properly with the RAG service. Along with these changes, there were also some issues with the existing functional, kernel, and unit tests.

Proposed resolution

The files that needs update are :-
- assistant.js
- AssistantChatForm.php
- KnowledgeAssistantSettingsForm.php
- ChatService.php

to make them compatible with the RAG service and fix the issues so that the functional, kernel, and unit tests pass.