Point the existing Info tile at PantallaTutorialAyuda (with
primerArranque: false, so its last page reads "Close") instead of
PluriOnboardingDialog's "what's new" modal.
Trade-off: PluriOnboardingDialog loses its only manual entry point --
it keeps auto-showing on its own existing cadence from app.dart, but
is no longer reachable by tapping this tile. This matches the mockup's
Info screen, which has no separate "what's new" row.