API (apps/api/src/routes/auth.ts):
- Exchange authorization code for tokens via Google's token endpoint
- Decode id_token payload (JWT) to extract sub, email, name
- Find user by googleId → fall back to email match (link accounts)
- Auto-create user if neither found (role: 'user', no password)
- Create session + set cookie, redirect to /login?token=<token>
Web (apps/web/src/pages/login-page.tsx):
- Consume ?token= query param from OAuth redirect
- Store token in localStorage for future API calls
- Fetch /auth/me to hydrate Zustand store, then navigate to dashboard
- Show OAuth errors from ?error= query param
Co-Authored-By: Claude <noreply@anthropic.com>
