fix: remove redundant cs_wallet lock around requestMempoolTransactions

The WITH_LOCK(cs_wallet, ...) wrapper around chain().requestMempoolTransactions()
creates a cs_wallet → cs_main lock ordering:

  requestMempoolTransactions acquires LOCK2(cs_main, mempool->cs), then calls
  transactionAddedToMempool which does LOCK(cs_wallet).

This is inconsistent with the typical cs_main → cs_wallet ordering and would
trigger DEBUG_LOCKORDER assertions.

The wrapper is unnecessary since transactionAddedToMempool acquires cs_wallet
internally per-transaction. Remove it.

Closes #7226

Author: thepastaclaw

src/node/interfaces.cpp

@@ -1477,9 +1477,16 @@ class ChainImpl : public Chain
     void requestMempoolTransactions(Notifications& notifications) override
     {
         if (!m_node.mempool) return;
-        LOCK2(::cs_main, m_node.mempool->cs);
-        for (const CTxMemPoolEntry& entry : m_node.mempool->mapTx) {
-            notifications.transactionAddedToMempool(entry.GetSharedTx(), /*nAcceptTime=*/0);
+        std::vector<CTransactionRef> txs;
+        {
+            LOCK2(::cs_main, m_node.mempool->cs);
+            txs.reserve(m_node.mempool->mapTx.size());
+            for (const CTxMemPoolEntry& entry : m_node.mempool->mapTx) {
+                txs.emplace_back(entry.GetSharedTx());
+            }
+        }
+        for (const auto& tx : txs) {
+            notifications.transactionAddedToMempool(tx, /*nAcceptTime=*/0);
         }
     }
     bool hasAssumedValidChain() override

src/wallet/wallet.cpp

@@ -2011,7 +2011,7 @@ CWallet::ScanResult CWallet::ScanForWalletTransactions(const uint256& start_bloc
     }
     if (!max_height) {
         WalletLogPrintf("Scanning current mempool transactions.\n");
-        WITH_LOCK(cs_wallet, chain().requestMempoolTransactions(*this));
+        chain().requestMempoolTransactions(*this);
     }
     ShowProgress(strprintf("%s " + _("Rescanning…").translated, GetDisplayName()), 100); // hide progress dialog in GUI
     if (block_height && fAbortRescan) {