Is your feature request related to a problem? Please describe.
No specific problem — this is a feature enhancement. Currently, the site supports GitHub and Discord login via NextAuth, but lacks Google login, which could improve accessibility and convenience for users.

Describe the solution you'd like
Added support for Google OAuth using NextAuth's built-in provider. This includes:

• Adding Google provider to [...nextauth].js.
• Two new environment variables: GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET.
• UI updates: Google login option appears alongside GitHub and Discord.
• Fully working and tested locally.

Describe alternatives you've considered

• Leaving authentication as-is with GitHub and Discord only.
• Adding other providers like Twitter or LinkedIn in the future.

Additional context

• Tested and confirmed working locally with a real Google OAuth app.
• I'd be happy to open a pull request for review if approved.