Version 0 testing

[reez]

• Cancel and track the in-flight NFC read task so a new scan or session invalidation can’t leave a runaway async job touching a stale NFCTagReaderSession.
  • NFC task management mirrors the pattern we’ve been using elsewhere (see 6f206a8) to avoid dead transports
• Skip card.dump for the active (sealed) SatsCard slot and reuse the status/address data instead; historical slots still get dumped as before, this avoids the panic path that occurs when CKTap omits the pubkey for a sealed slot, which was the root cause of the TestFlight crash reported in Version 0 testing #37.
  • I opened a PR on CKTap to address this fix: return slotsealed when dump omits pubkey bitcoindevkit/rust-cktap#49 so dump returns DumpError::SlotSealed instead of panicking, but this app-side guard keeps current builds stable and keeps us from issuing a doomed dump call even after the library is patched (might as well leave this in even after the library is patched)