vault_entries uses SQLite's space-separated UTC format everywhere, and both
sorting and sync last-write-wins compare the strings lexically — so a foreign
JSON import carrying strict-ISO 'T'/millis/Z/offset timestamps would slot in
with a different format and subtly break ordering and merge arbitration.
normalizeImportTimestamp converts any ISO-ish variant to 'YYYY-MM-DD
HH:MM:SS' UTC (bare strings treated as UTC, garbage -> '' = server stamps
now). +1 unit test (69 total).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
r-zakarya
829056f1fa