feat(activities): edit button on activity detail page

The NIP-52 d-tag we publish for an event is the LNbits event id (set
in nostr_publisher.build_nip52_event), so a single fetchMyEvents call
can tell us whether the displayed activity belongs to the caller.
When it does, show an Edit button next to Bookmark; clicking sets
the store's editingEvent and opens the shell-mounted dialog in edit
mode.

This was the missing surface — users land on /activities/:id when
they tap a posting, not on /events.

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

src/modules/activities/views/ActivityDetailPage.vue

@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { computed } from 'vue'
+import { computed, onMounted, ref, watch } from 'vue'
 import { useRoute, useRouter } from 'vue-router'
 import { useI18n } from 'vue-i18n'
 import { format } from 'date-fns'
@@ -8,13 +8,18 @@ import { Button } from '@/components/ui/button'
 import { Badge } from '@/components/ui/badge'
 import { Separator } from '@/components/ui/separator'
 import {
-  Calendar, MapPin, ArrowLeft,
+  Calendar, MapPin, ArrowLeft, Pencil,
 } from 'lucide-vue-next'
 import { useActivityDetail } from '../composables/useActivityDetail'
 import BookmarkButton from '../components/BookmarkButton.vue'
 import RSVPButton from '../components/RSVPButton.vue'
 import OrganizerCard from '../components/OrganizerCard.vue'
 import { NIP52_KINDS } from '../types/nip52'
+import { useAuth } from '@/composables/useAuthService'
+import { useActivitiesStore } from '../stores/activities'
+import { injectService, SERVICE_TOKENS } from '@/core/di-container'
+import type { TicketApiService } from '../services/TicketApiService'
+import type { TicketedEvent } from '../types/ticket'
 
 const route = useRoute()
 const router = useRouter()
@@ -24,6 +29,38 @@ const activityId = route.params.id as string
 const { activity, isLoading, error, reload } = useActivityDetail(activityId)
 const { dateLocale } = useDateLocale()
 
+// Owner-edit affordance: the NIP-52 d-tag we use for the activity id is
+// the same as the LNbits event id (set at publish time in
+// nostr_publisher.build_nip52_event). Look the user's own events up
+// once and offer an Edit button on a match.
+const { isAuthenticated, currentUser } = useAuth()
+const activitiesStore = useActivitiesStore()
+const ownedLnbitsEvent = ref<TicketedEvent | null>(null)
+
+async function loadOwnedEvent() {
+  ownedLnbitsEvent.value = null
+  if (!isAuthenticated.value) return
+  const invoiceKey = currentUser.value?.wallets?.[0]?.inkey
+  if (!invoiceKey) return
+  try {
+    const ticketApi = injectService(SERVICE_TOKENS.TICKET_API) as TicketApiService
+    const mine = await ticketApi.fetchMyEvents(invoiceKey)
+    ownedLnbitsEvent.value =
+      (mine as TicketedEvent[]).find((e) => e.id === activityId) ?? null
+  } catch {
+    ownedLnbitsEvent.value = null
+  }
+}
+
+onMounted(loadOwnedEvent)
+watch(isAuthenticated, () => loadOwnedEvent())
+
+function openEditDialog() {
+  if (!ownedLnbitsEvent.value) return
+  activitiesStore.editingEvent = ownedLnbitsEvent.value
+  activitiesStore.showCreateDialog = true
+}
+
 const dateDisplay = computed(() => {
   if (!activity.value) return ''
   const a = activity.value
@@ -60,11 +97,24 @@ function goBack() {
         <ArrowLeft class="w-4 h-4" />
         Back
       </Button>
-      <BookmarkButton
-        v-if="activity"
-        :pubkey="activity.organizer.pubkey"
-        :d-tag="activity.id"
-      />
+      <div class="flex items-center gap-1.5">
+        <Button
+          v-if="ownedLnbitsEvent"
+          variant="ghost"
+          size="sm"
+          class="gap-1.5"
+          @click="openEditDialog"
+          aria-label="Edit event"
+        >
+          <Pencil class="w-4 h-4" />
+          Edit
+        </Button>
+        <BookmarkButton
+          v-if="activity"
+          :pubkey="activity.organizer.pubkey"
+          :d-tag="activity.id"
+        />
+      </div>
     </div>
 
     <!-- Loading -->