feat: upgrade to v0.6.6 with improved tip transfer logic

src/trading/common/transaction_builder.rs

@@ -54,7 +54,7 @@ pub async fn build_transaction(
     instructions.extend(business_instructions);
 
     // Add tip transfer instruction
-    if with_tip {
+    if with_tip && tip_amount > 0.0 {
         instructions.push(transfer(
             &payer.pubkey(),
             tip_account,

src/trading/core/parallel.rs

@@ -110,7 +110,7 @@ async fn parallel_execute(
 
             let tip_account_str = swqos_client.get_tip_account()?;
             let tip_account = Arc::new(Pubkey::from_str(&tip_account_str).unwrap_or_default());
-            let tip_amount = priority_fee.buy_tip_fees[i];
+            let tip_amount = if with_tip { priority_fee.buy_tip_fees[i] } else { 0.0 };
 
             let transaction = build_transaction(
                 payer,