Snow Safari Reservation — Member Portal
This is the @ssr/web-mypage scaffold. Member dashboard, login/register, payment, reservation history, and points will be migrated here from apps/web in subsequent PRs.
Target sub-domain: mypage.reservation.snowsafari.co.jp
Auth: member authentication (Email/PW or Magic Link). Owns the NextAuth instance; reservation.snowsafari.co.jp shares this session via parent-domain Cookie.