fix(callflat): set ctx in live mode

Signed-off-by: jsvisa <delweng@gmail.com>

eth/tracers/native/call_flat.go

@@ -214,6 +214,14 @@ func (t *flatCallTracer) OnTxEnd(receipt *types.Receipt, err error) {
 	if t.interrupt.Load() {
 		return
 	}
+	if t.ctx == nil {
+		t.ctx = &tracers.Context{
+			BlockHash:   receipt.BlockHash,
+			BlockNumber: receipt.BlockNumber,
+			TxHash:      receipt.TxHash,
+			TxIndex:     int(receipt.TransactionIndex),
+		}
+	}
 	t.tracer.OnTxEnd(receipt, err)
 }