fix(chat): stop our own sent messages appearing as incoming duplicates

Two causes of the "every message I send shows up again as a reply from the peer":

1. Harvest bug — the full-refresh path fed a SENT tx's outgoing memos (from
   z_viewtransaction outgoing outputs) into the chat metadata extractor, and
   ChatService::ingest marks everything Incoming. So each send was re-ingested as
   a phantom "from peer" message. The recent-refresh path already omitted this, so
   it was accidental. Drop the outgoing chat-harvest (keep the tx-history harvest);
   genuine incoming still comes from z_listreceivedbyaddress, and our sends are
   recorded by the local echo.

2. Own-identity ingest filter — a memo whose sender public key equals our own
   identity is by definition something we sent (only we hold our key); it must
   never be ingested as incoming. Skip those in ingest. This also collapses
   same-seed self-chat (running the SAME wallet in the full node and Lite makes
   them one chat identity, so sends land on an address we also own and loop back).

For a real two-party chat use two DIFFERENT wallets/seeds — same-seed wallets are
one identity and can't be distinct peers.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/chat/chat_service.cpp

@@ -29,8 +29,16 @@ int ChatService::ingest(const std::vector<HushChatTransactionMetadata>& metadata
                         std::vector<std::string>* newIncomingCids) {
     if (!has_identity_) return 0;
 
+    const std::string myPubKey = chatIdentityPublicKeyHex(identity_);
+
     int added = 0;
     for (const auto& meta : metadata) {
+        // A memo whose sender is our OWN identity is something we sent (only we hold our key). The local
+        // echo already records it as outgoing — ingesting it as incoming would duplicate it as a phantom
+        // "from peer" message. (This also collapses same-seed self-chat, where the "peer" wallet shares
+        // our identity, so every message would otherwise loop back.)
+        if (!myPubKey.empty() && meta.sender_public_key_hex == myPubKey) continue;
+
         ChatMessage message;
         message.direction = ChatDirection::Incoming;
         message.txid = meta.txid;

src/services/network_refresh_service.cpp

@@ -168,20 +168,6 @@ void appendExtractedHushChatMetadata(std::vector<chat::HushChatTransactionMetada
     }
 }
 
-void appendExtractedHushChatMetadata(std::vector<chat::HushChatTransactionMetadata>& destination,
-                                     const std::string& txid,
-                                     const NetworkRefreshService::TransactionViewCacheEntry& entry)
-{
-    if (!chat::hushChatFeatureEnabledAtBuild()) return;
-
-    std::vector<chat::HushChatMemoOutput> outputs;
-    outputs.reserve(entry.outgoing_outputs.size());
-    for (const auto& output : entry.outgoing_outputs) {
-        if (!output.memo.empty()) outputs.push_back(chat::HushChatMemoOutput{output.position, output.memo});
-    }
-    appendExtractedHushChatMetadata(destination, txid, outputs);
-}
-
 void appendExtractedHushChatMetadata(std::vector<chat::HushChatTransactionMetadata>& destination,
                                      const HushChatMemoOutputMap& outputsByTxid)
 {
@@ -920,7 +906,10 @@ NetworkRefreshService::TransactionRefreshResult NetworkRefreshService::collectTr
         if (cached != snapshot.viewTxCache.end()) {
             if (!trackedSend || !cached->second.outgoing_outputs.empty()) {
                 appendViewTransactionOutputs(result.transactions, txid, cached->second);
-                appendExtractedHushChatMetadata(result.hushChatMetadata, txid, cached->second);
+                // NB: do NOT extract chat metadata from our OWN outgoing memos here — ingest marks
+                // everything Incoming, so that duplicates every sent message as a phantom "from peer"
+                // entry. Genuine incoming comes from the z_listreceivedbyaddress path; our sends are
+                // recorded by the local echo. (The recent-refresh variant already omits this.)
                 continue;
             }
         }
@@ -945,7 +934,8 @@ NetworkRefreshService::TransactionRefreshResult NetworkRefreshService::collectTr
 
             auto entry = parseViewTransactionCacheEntry(viewTransaction);
             appendViewTransactionOutputs(result.transactions, txid, entry);
-            appendExtractedHushChatMetadata(result.hushChatMetadata, txid, entry);
+            // (Chat metadata is harvested only from RECEIVED notes, not our own outgoing memos — see
+            // the cached-view branch above.)
 
             json rawTransaction;
             bool hasRawTransaction = false;