Add event list feature (009-list-events)

Enable users to see all their saved events on the home screen, sorted
by date with upcoming events first. Key capabilities:

- EventCard with title, relative time display, and organizer/attendee
  role badge
- Sortable EventList with past-event visual distinction (faded style)
- Empty state when no events are stored
- Swipe-to-delete gesture with confirmation dialog
- Floating action button for quick event creation
- Rename router param :token → :eventToken across all views
- useRelativeTime composable (Intl.RelativeTimeFormat)
- useEventStorage: add validation, removeEvent(), reactive versioning
- Full E2E and unit test coverage for all new components

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

frontend/src/views/EventStubView.vue

@@ -27,7 +27,7 @@ const route = useRoute()
 const copyState = ref<'idle' | 'copied' | 'failed'>('idle')
 
 const eventUrl = computed(() => {
-  return window.location.origin + '/events/' + route.params.token
+  return window.location.origin + '/events/' + route.params.eventToken
 })
 
 const copyLabel = computed(() => {