feat(get-me-a-chai/auth): add multi-provider login

[Swarnabha07]

Summary

Added multi-provider authorization (Google, Facebook, Linkedin) to the get-me-a-chai Next.js project under the sigma-web-dev-course repo.

Changes

• Updated app/api/auth/route.js to handle multiple providers.
• Updated app/(auth)/login-page.js for better sign-in handling.

How to test

1. Add environment variables to .env.local:

   • GOOGLE_CLIENT_ID
   • GOOGLE_CLIENT_SECRET
   • LINKEDIN_CLIENT_ID
   • LINKEDIN_CLIENT_SECRET
   • FACEBOOK_ID
   • FACEBOOK_SECRET
   • TWITTER_CLIENT_ID
   • TWITTER_CLIENT_SECRET
   • APPLE_ID
   • APPLE_SECRET
   • MONGODB_URI

2. Run the project:

   npm install
   npm run dev
   
   

3. Test sign-ins with all providers.