Implement authentication; support both manual email/password login and Google OAuth ### Acceptance Criteria - [ ] Users can log in manually (email/password) - [ ] Users can log in via Google OAuth - [ ] Authentication flow and UI match the attached designs - [ ] Successful login redirects to the portal dashboard under user identifier; logout ends the session and returns to the login screen
Implement authentication; support both manual email/password login and Google OAuth
Acceptance Criteria