IAV-1263/feat(public-tender): add scheduled BOAMP notifications for non-instant delivery
- Add scheduled notifications endpoints for n8n delivery: GET /scheduled-notifications/pending/user/{userUid} and PATCH /scheduled-notifications/{notificationUid}/mark-sent.
- Implement scheduled persistence flow (service + repository) that queues ScheduledNotifications rows with tender metadata for DAILY/WEEKLY alerts.
- BoampPollingScheduler: route alert handling by notification frequency (INSTANT -> webhook, DAILY/WEEKLY -> persist scheduled rows).
- AlertNotificationService: expose buildNotificationsForTenders(...) to reuse the same payload shape for instant webhook delivery and scheduled persistence.
- PublicMarketAgentRepository: fetch notificationConfig when loading active agents.
- PublicMarketWizardServiceImpl: inject API_BASE_URL placeholder in notification workflows.
- Add ALERT_SCHEDULED_NOTIFICATION_NOT_FOUND (PUBLIC-TENDER-SERVICE-053).