Sync change detection:
- DbConverters was using epochSecond but comparisons used epochMilli —
every file appeared modified on every scan, causing full re-sync each time
- DB migration 2→3 clears sync_file_states (all stored timestamps wrong)
- First sync after upgrade re-learns state; subsequent syncs skip unchanged files
Biometric:
- Move prompt trigger from LaunchedEffect to onResume() — guarantees
the activity is in RESUMED state when authenticate() is called
- Add bestAuthenticators(): tries BIOMETRIC_STRONG|DEVICE_CREDENTIAL first,
falls back to BIOMETRIC_WEAK|DEVICE_CREDENTIAL for side-sensor phones
- canAuthenticate() now accepts either strong or weak+credential
- onAuthenticationError always shows Unlock button (no infinite retry loop)
- isLocked/showRetry are Activity-level state, no need for Compose remember
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
