feat(nostr): NIP-50 search via relay.nostr.band and nostr.wine (M11.7)

Search input sends REQ with search field to NIP-50 supporting relays.
Results shown as note cards with author, content, timestamp. Filter
by content type. NIP-50 button triggers relay search on Enter.

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

packages/app/src/composables/useNostr.ts

@@ -282,6 +282,85 @@ function importNIP65Relays(event: NostrEvent) {
   }
 }
 
+const NIP50_RELAYS = [
+  'wss://relay.nostr.band',
+  'wss://nostr.wine',
+]
+
+const searchResults = shallowRef<NostrNote[]>([])
+const isSearching = ref(false)
+
+function searchNostr(query: string, kinds?: number[]): void {
+  if (!query.trim()) {
+    searchResults.value = []
+    return
+  }
+
+  isSearching.value = true
+  searchResults.value = []
+
+  const subId = generateSubId()
+  const filter: Record<string, unknown> = { search: query, limit: 50 }
+  if (kinds && kinds.length > 0) filter.kinds = kinds
+
+  const results: NostrNote[] = []
+  let closedCount = 0
+
+  for (const relayUrl of NIP50_RELAYS) {
+    try {
+      const ws = new WebSocket(relayUrl)
+      const timer = setTimeout(() => {
+        ws.close()
+      }, 8000)
+
+      ws.onopen = () => {
+        ws.send(JSON.stringify(['REQ', subId, filter]))
+      }
+
+      ws.onmessage = (msg) => {
+        try {
+          const data = JSON.parse(msg.data)
+          if (Array.isArray(data) && data[0] === 'EVENT' && data[1] === subId && data[2]) {
+            const evt = data[2] as NostrEvent
+            if (!results.find(r => r.id === evt.id)) {
+              results.push({
+                id: evt.id,
+                pubkey: evt.pubkey,
+                authorName: truncatePubkey(evt.pubkey),
+                kind: evt.kind,
+                content: evt.content,
+                created_at: evt.created_at,
+                tags: evt.tags ?? [],
+              })
+              searchResults.value = [...results].sort((a, b) => b.created_at - a.created_at)
+            }
+          }
+          if (Array.isArray(data) && data[0] === 'EOSE' && data[1] === subId) {
+            clearTimeout(timer)
+            ws.close()
+          }
+        } catch { /* skip */ }
+      }
+
+      ws.onclose = () => {
+        closedCount++
+        if (closedCount >= NIP50_RELAYS.length) {
+          isSearching.value = false
+        }
+      }
+
+      ws.onerror = () => {
+        clearTimeout(timer)
+      }
+    } catch {
+      closedCount++
+      if (closedCount >= NIP50_RELAYS.length) {
+        isSearching.value = false
+      }
+    }
+  }
+}
+
 export interface PublishResult {
   url: string
   success: boolean
@@ -388,6 +467,9 @@ export function useNostr() {
     disconnect,
     fetchNote,
     publishEvent,
+    searchResults,
+    isSearching,
+    searchNostr,
     addRelay,
     removeRelay,
     toggleRelayRead,