Phase 1 cached only notes. Phase 2 brings the read-through pattern to every
domain the app reads in bulk:
- Drift schema v2: 5 new cached_* tables + onUpgrade migration. Calendar
events use range-scoped read/write (replaceEventsInRange) so disjoint
month fetches don't clobber each other; milestones are per-project.
- Wrap TasksRepository, ProjectsRepository, MilestonesRepository, and
ChatRepository (conversation list only) with NetworkException fallback.
Writes hit the API then sync the cache.
- New EventsRepository wrapping EventsApi; calendar_provider and
event_form_sheet repointed at the repository.
- OfflineBanner now surfaces getLatestSync() — most-recent timestamp
across all domains — so the hint reads sensibly regardless of screen.
flutter analyze clean; existing tests pass. Phase 3 (offline write queue)
and Phase 4 (read-only UI indicators) still to come.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
bvandeusen