- Add promo banner illustration (assets/images/invite_friends_promo_banner.webp)
and replace the empty placeholder box in FollowersPromoBanner.
- Redirect the followers empty-state banner to the Find and Invite Friends
settings screen instead of opening the share sheet, gated to mirror that
screen's availability (native, geolocation allowlist, feature flag) so we
don't promote contact import where the settings entry is hidden.
- Drop the now-dead invite dialog mount/control from ProfileFollowers and
update the banner a11y copy to match the new destination.
- Scanner: collapse the unused error-message state to a boolean (the overlay
renders its own localized copy).