Security hardening from the pre-external-TestFlight audit (2026-04-17):

• Keychain nsec is now ThisDeviceOnly — not included in encrypted device backups
• Clipboard copies of nsec + bunker URI disable Universal Clipboard and auto-expire after 2 min
• Kind:22242 (NIP-42 relay auth) now requires client pairing first; fixes an
  unpaired-signing vulnerability (audit D.5.1)
• sign_event permission check now fails closed on malformed event kind (audit D.5.2)
• APNs device token no longer logged with public privacy level
• New LightSigner.peekMethod helper enables batch-sort of connect requests
  in NSE, preventing the race that required the kind:22242 bypass

Full audit report (coming soon) will be published under security-audits/.