Records created before Task 16 (per-stage Datetime fields + write
snapshot hook) have NULL for received_at/shipped_at/etc. SQL backfill
copies received_date -> received_at; this commit adds a runtime
fallback so if any record slips through (manual edits, future
imports) the timeline still surfaces what's available.
Also render date-only ('May 16, 2026') when the timestamp has no
time component, so backfilled-from-Date records don't show the
misleading 'may 16 · 12:00a' fake time.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>