feat: T4 wave 3 - notifications per user, suggestions API, varroa bands, split/queen events

- Schema III: per-user notifications (broadcast fan-out migration,
  category, link, requiredPermissions filter), notification preferences
  and settings endpoints, calendar withdrawal switch, occupiedFrames
- Suggestions API: list/summary with permission visibility and paging,
  accept/dismiss/reopen incl. bulk, SuggestionView on all responses
- Varroa traffic light by season and method, young colonies, treatment
  effect window, sample-based percentage; shared withdrawal-window helper
  on Berlin calendar days; GET /varroa-measurements/thresholds
- ColonySplit and QueenAssigned domain events with calendar and webhook
  handlers
- Outbox claims compare against now() rounded to timestamp(3); fixes the
  flaky e2e claims of rows written with SQL now()

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

ApiCore-Backend/test/treatments.e2e-spec.ts

@@ -260,7 +260,7 @@ describe('Treatments (e2e)', () => {
 
     it('accepts a full ISO timestamp', async () => {
       await expect(
-        withdrawalStatusAt('2026-07-14T23:59:59.000Z'),
+        withdrawalStatusAt('2026-07-14T23:59:59+02:00'),
       ).resolves.toHaveLength(1);
     });