[SECURITY]: The JWT token is stored in the local-storage.

I just noticed that after logging in to the DebateAI, the jwt token is getting stored into the local storage, and i had heard from sources that storing the token in the local storage is not safe. But I got to know that the token's only payload is `email` but still it's not safe, I visited the auth0 official docs (https://auth0.com/docs/secure/security-guidance/data-security/token-storage#don-t-store-tokens-in-local-storage) and even they does not guide to store the tokens in local storage, due to a cross-site scripting (XSS) attack.

Changes we need to get back to a secure auth -
- set `credientials: true` in frontend and CORS.
- Setting and reading HTTP-only cookies
- Correcting the CORS config.