Service 2: OAuth Integration (Google & GitHub)

Objective

Allow login via Google and GitHub OAuth.

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Google OAuth Flow

• GET /api/oauth/google → initiate OAuth
• GET /api/oauth/google/callback → handle callback and JWT issuance

GitHub OAuth Flow

• GET /api/oauth/github → initiate OAuth
• GET /api/oauth/github/callback → handle callback and JWT issuance

OAuth User Linking

• Link OAuth accounts to existing users if email exists.
• Auto-create new user if no account exists.