f568c0aeb7
- Add SseEmitterRegistry (ConcurrentHashMap, one emitter per user) - Add GET /api/notifications/stream SSE endpoint and unread-count endpoint - Push SSE event on every notifyReply / notifyMentions via saveAndPush() - Collapse V18/V19 migrations into V16 (actor_name + annotation_id upfront) - Add @Schema(requiredMode=REQUIRED) to NotificationDTO required fields - Switch NotificationBell from polling to EventSource; seed unread count on open - Fix MentionEditor: replace setTimeout with await tick(); div role=option - Add aria-modal=true to NotificationBell dialog - Tests: SseEmitterRegistryTest (3), NotificationServiceTest (+2), NotificationControllerTest (+5) Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>