Add a fact checker feature with updated styling (#835)

- Add an experimental feature used for fact-checking falsifiable statements with customizable models. See attached screenshot for example. Once you input a statement that needs to be fact-checked, Khoj goes on a research spree to verify or refute it.
- Integrate frontend libraries for [Tailwind](https://tailwindcss.com/) and [ShadCN](https://ui.shadcn.com/) for easier UI development. Update corresponding styling for some existing UI components. 
- Add component for model selection 
- Add backend support for sharing arbitrary packets of data that will be consumed by specific front-end views in shareable scenarios

src/interface/web/app/components/chatHistory/chatHistory.tsx

@@ -40,6 +40,7 @@ export default function ChatHistory(props: ChatHistoryProps) {
                 setLoading(false);
                 // Render chat options, if any
                 if (chatData) {
+                    console.log(chatData);
                     setData(chatData.response);
                 }
             })