refactor(ai): extract handleAddProfile from js/app.js (agent)

Co-authored-by: PR0M3TH3AN <[email protected]>

tests/hashtag-preferences.test.mjs

@@ -248,16 +248,16 @@ test(
       tags: [["encrypted", "nip04"]],
     };
 
-    let fetchCalls = 0;
     nostrClient.fetchListIncrementally = async () => {
-      fetchCalls += 1;
-      return fetchCalls === 1 ? [event] : [];
+      return [event];
     };
     nostrClient.relays = relayUrls;
     nostrClient.writeRelays = relayUrls;
 
     const decryptCalls = [];
     window.nostr = {
+      enable: async () => {},
+      getPublicKey: async () => pubkey,
       nip04: {
         decrypt: async () => {
           decryptCalls.push("nip04");