chore(activities): reroute CreateActivityDialog through TicketApiService.createEvent

The aiolabs/events extension on its signer-abstraction branch (commit
66076d6) constructs and publishes kind-31922 NIP-52 calendar events
server-side via NostrSigner — POST /events/api/v1/events accepts a
CreateEventRequest payload, signs through the operator's signer, and
broadcasts to configured relays. The webapp no longer needs to sign
calendar events client-side.

Changes:
- ActivitiesNostrService.ts: delete publishCalendarEvent() and its
  helper imports (finalizeEvent, EventTemplate, buildCalendarTimeEventTags,
  the local hexToUint8Array). The subscribe / query paths stay — the
  service still reads NIP-52 events off relays for the activity feed.
  Docstring updated to reflect the read-only role and point at the
  events extension for the publish path.
- CreateActivityDialog.vue: swap the publish flow.
  - Drop ActivitiesNostrService injection + currentUser.value.prvkey read.
  - Inject TicketApiService instead; pull invoiceKey from
    currentUser.value.wallets[0].inkey (same pattern as EventsPage.vue
    handleCreateEvent).
  - Build CreateEventRequest with amount_tickets: 0, price_per_ticket: 0
    (events extension treats 0 as unlimited/not-ticketed per
    models.py:45-46 per lnbits 22:30Z audit).
  - Fold summary + description into the events extension's `info`
    field since CreateEventRequest has no separate summary slot.
  - Update toast on success to "Activity created!" (server publishes
    to relays via the signer, not the webapp).

Approval-workflow caveat documented inline in the submit handler:
non-admin users on instances with auto_approve=false (the default)
land in the proposal queue and don't publish to relays until an admin
approves. Admins / auto_approve=true instances publish immediately.
This is the intended new behavior — operators can flip auto_approve
on the events extension config per-instance if they want the legacy
direct-publish moderation posture.

This is webapp's second bucket-A leg per aiolabs/lnbits#9 phase-1.
The remaining `currentUser.value.prvkey` reads stay until the
atomic User.prvkey field-removal PR (Q1.2 Option (b)).

Refs:
- log:2026-05-28T22:30Z (lnbits Q2.1 audit verifying ticket-less
  acceptance + approval-workflow caveat)
- ~/dev/coordination/webapp-design-questions.md Q2.1
- aiolabs/events signer-abstraction commit 66076d6 (the server-side
  publish path)
- aiolabs/lnbits cascade tip 861f427c deployed to aio-demo

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/modules/activities/composables/useActivityDetail.ts

@@ -32,18 +32,24 @@ export function useActivityDetail(activityId: string) {
       isLoading.value = true
       error.value = null
 
-      // Subscribe and wait for this specific event
+      // Scope both the subscription and the one-shot query to this
+      // activity's d-tag. Without this scope, the query asks every
+      // relay for every kind-31922/31923 event and races a 5s timeout
+      // to find ours — on a cold page refresh that race is often lost
+      // even when the activity is reachable.
+      const detailFilters = { dTags: [activityId] }
+
       unsubscribe = nostrService.subscribeToCalendarEvents(
         (incoming) => {
           store.upsertActivity(incoming)
           if (incoming.id === activityId) {
             isLoading.value = false
           }
-        }
+        },
+        detailFilters
       )
 
-      // Also do a one-shot query
+      const results = await nostrService.queryCalendarEvents(detailFilters)
-      const results = await nostrService.queryCalendarEvents()
       store.upsertActivities(results)
 
       // If we still don't have it after query, stop loading

src/modules/activities/services/ActivitiesNostrService.ts

@@ -23,6 +23,8 @@ export interface CalendarEventFilters {
   hashtags?: string[]
   /** Filter by geohash prefix (NIP-52 'g' tag) */
   geohash?: string
+  /** Filter by NIP-52 'd' tag — scopes the query to specific parameterized-replaceable events */
+  dTags?: string[]
 }
 
 /**
@@ -148,6 +150,7 @@ export class ActivitiesNostrService extends BaseService {
     if (filters?.authors?.length) filter.authors = filters.authors
     if (filters?.hashtags?.length) filter['#t'] = filters.hashtags
     if (filters?.geohash) filter['#g'] = [filters.geohash]
+    if (filters?.dTags?.length) filter['#d'] = filters.dTags
 
     return [filter]
   }