[Feature]: Add Google Authentication for Login/Signup

[Dev1822]

Area

Authentication / onboarding

Problem to solve

Currently, users can only sign up or log in using traditional email/password methods. This process is time-consuming and can act as a barrier for new users, potentially leading to higher drop-off rates during onboarding.

Proposed solution

Integrate Google Authentication using OAuth 2.0. We need to add a "Continue with Google" button on the frontend (login and signup pages). On the backend, we need to implement logic to verify Google tokens, securely retrieve user information, and either register a new account or log in an existing user.

Who benefits and how?

New and returning users will benefit from a faster, seamless, and more secure onboarding experience without needing to create or remember another password.

Scope or acceptance criteria

• Google OAuth 2.0 project configured with client IDs and secrets in environment variables.
• Frontend UI updated with a functional "Continue with Google" button.
• Backend endpoints added to receive and verify Google tokens.
• User accounts are successfully created or retrieved based on Google credentials.
• Proper error handling implemented (e.g., if a user cancels the flow or the token is invalid).

Related files, routes, or references

frontend/src/pages/Login.jsx (or equivalent)
frontend/src/pages/Signup.jsx (or equivalent)
server/routes/auth.js (or equivalent)
server/controllers/auth.js (or equivalent)

Before submitting

• I checked for an existing issue that already covers this request.

I would like to work on this issue if assigned