S1 made NotificationRecipient.EmailAddress nullable + added SmsConfiguration
and four INotificationRepository SMS methods, breaking compilation beyond the
intentionally-deferred central NotificationRepository.
Fix 1 (CS8620/CS8604 nullable EmailAddress projections, email-only paths):
- NotificationOutbox EmailNotificationDeliveryAdapter: filter non-null emails
- DeploymentManager ArtifactDeploymentService: filter non-null emails
- Transport EntitySerializer: filter non-null emails into NotificationRecipientDto
Fix 2 (CS0535): stub the four SMS-config methods on SiteRuntime
SiteNotificationRepository (central-only — NotSupportedException, matching the
existing 'Managed via artifact deployment from Central' write-path pattern).
Doc nits: reword NotificationRecipient private ctor and SmsConfiguration.AuthToken
comments.
The central ConfigurationDatabase.NotificationRepository compile break is left
as-is (S2 implements those four methods).