feat: member portal Sprint 4 — Events + RSVP

- Event + EventRsvp models + migration (RsvpStatus enum: GOING/MAYBE/NOT_GOING)
- EventsModule: admin CRUD (create/update/delete/publish) + RSVP list
- GET /my/events + POST /my/events/:id/rsvp in MyController/MyService
- Admin BFF routes: GET/POST /api/admin/events, PATCH/DELETE /api/admin/events/[id]
- Member BFF routes: GET /api/my/events, POST /api/my/events/[id]/rsvp
- /my/events page: upcoming/past split, RSVP button (client component, optimistic)
- Register DigestModule, OrgModule, ThreadsModule, EventsModule in AppModule
- Add EVENT_CREATED/DELETED/UPDATED and DIGEST_SENT to AuditAction

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/web/app/my/layout.tsx

@@ -5,6 +5,7 @@ import { redirect } from 'next/navigation';
 const NAV = [
   { href: '/my', label: 'Dashboard' },
   { href: '/my/digest', label: 'Digest' },
+  { href: '/my/events', label: 'Events' },
   { href: '/my/groups', label: 'My Groups' },
   { href: '/my/settings', label: 'Settings' },
 ];