feat(events): markdown body, registered indicator, drop capacity counters

- Public event detail page renders description/series-description/content
  as markdown via useMarkdown, with prose styles; agenda becomes an
  unordered list with the same custom bullets.
- Events list API returns `isRegistered` per event (derived from the
  requester's registrations, ignoring cancelled rows), and the list page
  shows a "Registered" tag. Stops exposing the full registrations array
  in the list response.
- Removes the seats/sold-out/limited capacity UI from list and detail
  pages.
- EventTicketPurchase: minor template formatting (self-closing inputs,
  prettier wrapping).

app/pages/events/[slug].vue

@@ -30,10 +30,6 @@
         <div v-if="event.circle" class="event-meta-item">
           <CircleBadge :circle="event.circle" />
         </div>
-        <div v-if="event.maxAttendees" class="event-meta-item">
-          <span class="meta-label">Capacity</span>
-          {{ event.registeredCount || 0 }}/{{ event.maxAttendees }} seats
-        </div>
       </div>
     </div>
 
@@ -85,7 +81,7 @@
         <!-- Description -->
         <div class="section">
           <h2>About This Event</h2>
-          <p>{{ event.description }}</p>
+          <div class="prose" v-html="renderMarkdown(event.description)" />
         </div>
 
         <!-- Series Description -->
@@ -94,17 +90,23 @@
           class="section"
         >
           <h2>About the {{ event.series.title }} Series</h2>
-          <p>{{ event.series.description }}</p>
+          <div class="prose" v-html="renderMarkdown(event.series.description)" />
+        </div>
+
+        <!-- Additional Information -->
+        <div v-if="event.content" class="section">
+          <h2>Additional Information</h2>
+          <div class="prose" v-html="renderMarkdown(event.content)" />
         </div>
 
         <!-- Agenda -->
         <div v-if="event.agenda?.length" class="section">
           <h2>Agenda</h2>
-          <ol class="agenda-list">
+          <ul class="agenda-list">
             <li v-for="(item, index) in event.agenda" :key="index">
               {{ item }}
             </li>
-          </ol>
+          </ul>
         </div>
 
         <!-- Speakers -->
@@ -143,7 +145,7 @@
           <div class="box-title">Event Details</div>
           <div v-if="event.eventType" class="detail-row">
             <span class="detail-key">Type</span>
-            <span class="detail-val">{{ event.eventType }}</span>
+            <span class="detail-val">{{ eventTypeLabel(event.eventType) }}</span>
           </div>
           <div v-if="event.membersOnly" class="detail-row">
             <span class="detail-key">Members only</span>
@@ -169,6 +171,8 @@
 </template>
 
 <script setup>
+import { eventTypeLabel } from "~/config/eventTypes";
+
 const route = useRoute();
 const toast = useToast();
 
@@ -190,6 +194,7 @@ if (error.value?.statusCode === 404) {
 
 const { memberData, checkMemberStatus } = useAuth();
 const { trackGoal, isComplete } = useOnboarding();
+const { render: renderMarkdown } = useMarkdown();
 
 onMounted(async () => {
   await checkMemberStatus();
@@ -232,16 +237,12 @@ const handleTicketError = (err) => {
   console.error("Ticket purchase failed:", err);
 };
 
-useHead(() => ({
-  title: event.value
-    ? `${event.value.title} - Ghost Guild Events`
-    : "Event - Ghost Guild",
-  meta: [
-    {
-      name: "description",
-      content: event.value?.description || "View event details and register",
-    },
-  ],
+useSiteMeta(() => ({
+  title: event.value ? `${event.value.title} · Events` : "Event",
+  description:
+    event.value?.description || "View event details and register.",
+  type: "article",
+  image: event.value?.slug ? `/og/events/${event.value.slug}.png` : undefined,
 }));
 </script>
 
@@ -349,12 +350,79 @@ useHead(() => ({
   margin-bottom: 8px;
 }
 .section p {
-  font-size: 12px;
+  font-size: 14px;
   color: var(--text-dim);
   line-height: 1.7;
   max-width: 560px;
 }
 
+.prose {
+  font-size: 14px;
+  color: var(--text-dim);
+  line-height: 1.7;
+  max-width: 560px;
+}
+.prose :deep(p) {
+  margin-bottom: 12px;
+}
+.prose :deep(p:last-child) {
+  margin-bottom: 0;
+}
+.prose :deep(a) {
+  color: var(--ember);
+  text-decoration: underline;
+  text-underline-offset: 2px;
+}
+.prose :deep(strong) {
+  color: var(--text-bright);
+}
+.prose :deep(ul),
+.prose :deep(ol) {
+  list-style: none;
+  padding: 0;
+  margin: 8px 0 12px;
+}
+.prose :deep(ul li),
+.prose :deep(ol li) {
+  position: relative;
+  padding: 2px 0 2px 16px;
+  margin-bottom: 4px;
+}
+.prose :deep(ul li::before) {
+  content: "›";
+  position: absolute;
+  left: 0;
+  top: 2px;
+  color: var(--candle-faint);
+  font-size: 14px;
+  line-height: 1.7;
+}
+.prose :deep(ol) {
+  counter-reset: prose-item;
+}
+.prose :deep(ol li) {
+  counter-increment: prose-item;
+  padding-left: 28px;
+}
+.prose :deep(ol li::before) {
+  content: counter(prose-item) ".";
+  position: absolute;
+  left: 0;
+  top: 2px;
+  color: var(--candle-faint);
+}
+.prose :deep(blockquote) {
+  border-left: 2px solid var(--candle-faint);
+  padding-left: 12px;
+  margin: 12px 0;
+  color: var(--text-faint);
+}
+.prose :deep(code) {
+  font-family: "Commit Mono", monospace;
+  background: var(--input-bg);
+  padding: 0 4px;
+}
+
 .circle-badges {
   display: flex;
   gap: 6px;
@@ -367,10 +435,27 @@ useHead(() => ({
 }
 
 .agenda-list {
-  padding-left: 20px;
-  font-size: 12px;
+  list-style: none;
+  padding: 0;
+  margin: 8px 0 0;
+  font-size: 14px;
   color: var(--text-dim);
-  line-height: 2;
+  line-height: 1.7;
+  max-width: 560px;
+}
+.agenda-list li {
+  position: relative;
+  padding: 2px 0 2px 16px;
+  margin-bottom: 4px;
+}
+.agenda-list li::before {
+  content: "›";
+  position: absolute;
+  left: 0;
+  top: 2px;
+  color: var(--candle-faint);
+  font-size: 14px;
+  line-height: 1.7;
 }
 
 .speaker {