feat: warn when txCount != 1 (#3644)

cw_monero/lib/api/structs/pending_transaction.dart

@@ -4,11 +4,13 @@ class PendingTransactionDescription {
       required this.fee,
       required this.hash,
       required this.hex,
-      required this.pointerAddress});
+      required this.pointerAddress,
+      required this.txCount});
 
   final int amount;
   final int fee;
   final String hash;
   final String hex;
   final int pointerAddress;
+  final int txCount;
 }

cw_monero/lib/api/transaction_history.dart

@@ -219,6 +219,7 @@ Future<PendingTransactionDescription> createTransactionSync(
     fee: rFee,
     hash: rHash,
     hex: rHex,
+    txCount: pendingTx.txCount(),
     pointerAddress: pendingTx.ffiAddress(),
   );
 }
@@ -263,6 +264,7 @@ Future<PendingTransactionDescription> createTransactionMultDest(
     hash: tx.txid(''),
     hex: tx.hex(''),
     pointerAddress: tx.ffiAddress(),
+    txCount: tx.txCount(),
   );
 }
 

cw_monero/lib/monero_wallet.dart

@@ -491,7 +491,10 @@ abstract class MoneroWalletBase
           paymentId: '');
     }
 
-    // final status = monero.PendingTransaction_status(pendingTransactionDescription);
+    if (pendingTransactionDescription.txCount != 1) {
+      throw MoneroTransactionCreationException(
+          "This payment would be split into ${pendingTransactionDescription.txCount} transactions. Send smaller transaction to yourself first.",);
+    }
 
     return PendingMoneroTransaction(pendingTransactionDescription, this);
   }