feat: T4 wave 6 - reminders and morning digest, next steps UI, warnings and notifications UI

- In-app reminders: task due (skips rescheduled tasks, catch-up wording)
  and a per-user morning digest step in the daily job
- Frontend: "Als Nächstes" on the colony page, "Heute" on the dashboard,
  inspection-due card, season chip, apiary overview fields, cleanup
  sheet for ended colonies
- Frontend: plausibility warnings that stay until dismissed, withdrawal
  spans in the calendar, notification bell with categories and links,
  notification settings in the profile
- ARCHITECTURE.md: T4a sections 11.1-11.10, assumptions 31-41, handler
  table and daily job step order

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

ApiCore-Backend/test/worker-runtime.e2e-spec.ts

@@ -200,10 +200,16 @@ describe('Worker runtime (e2e)', () => {
       where: { aggregateId: `${suffix}-0` },
       include: { deliveries: true },
     });
-    expect(event).toMatchObject({
-      status: 'DONE',
-      deliveries: [{ handler: 'test.worker-counter', status: 'DONE' }],
-    });
+    // TaskDue also has the real reminder handler (the task does not exist: a no-op).
+    expect(event.status).toBe('DONE');
+    expect(
+      event.deliveries.map(({ handler, status }) => ({ handler, status })),
+    ).toEqual(
+      expect.arrayContaining([
+        { handler: 'test.worker-counter', status: 'DONE' },
+        { handler: 'notifications.task-due', status: 'DONE' },
+      ]),
+    );
   });
 
   it('wakes the calendar outbox loop on a calendar_sync notification', async () => {