Account menu + mobile top bar Navigation redesign. Perfil is no longer a permanent tab: personal actions (Perfil, Admin, Cerrar sesión) now live behind a "Cuenta" menu, keeping the bar for the frequent destinations. - Mobile: fixed top bar (logo + account); bottom bar keeps the content tabs (Viajes, Conversor). - Desktop: brand left, options centered, account pinned right. - Logout centralized in Session.logout(), shared by profile + nav. - UI polish: title sizes and FAB clearance tuned for the top bar.