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/src/reminders/digest.step.ts

@@ -0,0 +1,21 @@
+import { Injectable } from '@nestjs/common';
+import type { DailyEvaluationStep } from '../jobs/daily-evaluation-steps';
+import type { JobResult } from '../jobs/job';
+import { DigestService } from './digest.service';
+
+/**
+ * Step "digest", the last of the daily evaluation: the in-app morning
+ * digest of every user. Running it twice for one day writes nothing the
+ * second time (the key holds the day and the user): `digestsWritten` is 0
+ * on a same-day rerun.
+ */
+@Injectable()
+export class DigestStep implements DailyEvaluationStep {
+  readonly name = 'digest';
+
+  constructor(private readonly digests: DigestService) {}
+
+  async run(today: string): Promise<JobResult> {
+    return { digestsWritten: await this.digests.runFor(today) };
+  }
+}