[Bug]: Authentication not working

[indrasuthar07]

Description

• The main issue is that the frontend uses mock authentication instead of calling the backend API.
• Even if the backend works, the frontend never sends real requests, doesn't store tokens, and doesn't manage authentication state.
• The backend also has inconsistencies in JWT secrets and token structure that would cause problems once connected.
• and all pages like browse and sell are accessible without login that doesn't make sense of login's existing.

Code of Conduct

• I agree to follow this project's Code of Conduct

[indrasuthar07]

@04shubham7 sir i have already solved the bug, assign it to me so i can raise a pr