## Summary
- redirect guest access to protected routes based on returning-user
cookie
- send new PWA guests to registration and returning guests to login
- persist returning-user cookie after register, login, and 2FA login
- keep explicit login links working via `force=1`
## Testing
- vendor/bin/pint --dirty --format agent
- php artisan test --compact tests/Feature/Auth/AuthenticationTest.php
tests/Feature/DashboardTest.php tests/Feature/Auth/RegistrationTest.php
## Summary
- store browser-detected IANA timezones on users during registration and
share the value to the frontend
- silently backfill missing timezones for authenticated users without
overwriting existing saved values
- add focused feature coverage for registration, shared props, and the
timezone backfill endpoint
## Testing
- php artisan test --compact tests/Feature/Auth/RegistrationTest.php
tests/Feature/InertiaSharedDataTest.php
tests/Feature/Settings/TimezoneTest.php
- npm test -- resources/js/utils/currency.test.ts