Check-in Mobile

### Added - Participant profile can now show custom answers: Choose which registration answers to display, per event, on aanmelder.nl. Use this when your check-in staff need to see specific answers, like meal preferences or workshop choices, right on the participant's profile. ### Changed - Significant overhaul of the barcode scanner logic. ### Removed - Participants with a pending or expired payment; they no longer appear in the participant list, check-in counts, or QR-code scan lookup — only registered participants are shown and can be checked in. ### Fixed - Slowdown after prolonged use with continuous scanning enabled. - Stale "communicating with server" animation when the "Start initial sync" action in Settings fails with an error.