Notification fixes:
- Add NotificationToaster component with real-time toast notifications
for new incoming notifications (30s polling, 15s stale time)
- Connection request toasts show inline Accept/Reject buttons
- Add inline Accept/Reject buttons to connection_request notifications
in NotificationsPage (prevents bricked requests after navigation)
- Don't mark connection_request as read or navigate away when pending
- Auto-refetch notification list when unread count increases
Admin panel fixes:
- Add error state UI to UserDetailSection and ConfigPage (previously
silently returned null/empty on API errors)
- Fix get_user response missing must_change_password and locked_until
- Fix create_user response missing preferred_name and date_of_birth
- Add defensive limit(1) on settings query to prevent MultipleResultsFound
- Guard _target_username_col JSONB cast with CASE to prevent crash on
non-JSON audit detail values
- Add connection audit action types to ConfigPage filter dropdown
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>