nip46: omit custodial bunker providers that don't have relays configured.

nip46.ts

@@ -93,6 +93,10 @@ export class BunkerSigner {
    * @param secretKey - An optional key pair.
    */
   public constructor(clientSecretKey: Uint8Array, bp: BunkerPointer, params: BunkerSignerParams = {}) {
+    if (bp.relays.length === 0) {
+      throw new Error('no relays are specified for this bunker')
+    }
+
     this.pool = params.pool || new SimplePool()
     this.secretKey = clientSecretKey
     this.relays = bp.relays
@@ -242,25 +246,23 @@ export async function createAccount(
 }
 
 /**
- * Fetches info on available signers (nsecbunkers) using NIP-89 events.
- *
+ * Fetches info on available providers that announce themselves using NIP-89 events.
  * @returns A promise that resolves to an array of available bunker objects.
  */
 export async function fetchCustodialbunkers(pool: AbstractSimplePool, relays: string[]): Promise<BunkerProfile[]> {
-  const events = await pool.querySync(relays, { kinds: [Handlerinformation] })
-  // filter for events that handle the connect event kind
-  const filteredEvents = events.filter(event =>
-    event.tags.some(tag => tag[0] === 'k' && tag[1] === NostrConnect.toString()),
-  )
+  const events = await pool.querySync(relays, {
+    kinds: [Handlerinformation],
+    '#k': [NostrConnect.toString()],
+  })
 
-  // Validate bunkers by checking their NIP-05 and pubkey
-  // Map to a more useful object
+  // validate bunkers by checking their NIP-05 and pubkey
+  // map to a more useful object
   const validatedBunkers = await Promise.all(
-    filteredEvents.map(async event => {
+    events.map(async event => {
       try {
         const content = JSON.parse(event.content)
         const bp = await queryBunkerProfile(content.nip05)
-        if (bp && bp.pubkey === event.pubkey) {
+        if (bp && bp.pubkey === event.pubkey && bp.relays.length) {
           return {
             bunkerPointer: bp,
             nip05: content.nip05,