feat: Add zero-padding to transaction flow numbering for better alignment

internal/tui/model.go

@@ -1390,6 +1390,14 @@ func (m *Model) updateCallDetailView() {
 
 	// --- Transaction Flow ---
 	var right strings.Builder
+	// Calculate padding needed
+	digits := len(fmt.Sprintf("%d", len(flow.Packets)))
+	if digits < 2 {
+		digits = 2
+	}
+	// Pad format string e.g. "%03d."
+	numFmt := fmt.Sprintf("%%0%dd.", digits)
+
 	for i, pkt := range flow.Packets {
 		arrow := "→"
 		arrowStyle := m.styles.ArrowOut
@@ -1428,7 +1436,9 @@ func (m *Model) updateCallDetailView() {
 		}
 
 		ts := pkt.Timestamp.Format("15:04:05.000")
-		lineStr := fmt.Sprintf("%d. [%s] %s %s", i+1, ts, arrowStyle.Render(arrow), summaryStyle.Render(pkt.Summary()))
+		// Use pre-calculated format
+		numStr := fmt.Sprintf(numFmt, i+1)
+		lineStr := fmt.Sprintf("%s [%s] %s %s", numStr, ts, arrowStyle.Render(arrow), summaryStyle.Render(pkt.Summary()))
 
 		if pkt.SDP != nil {
 			mediaIP := pkt.SDP.GetSDPMediaIP()
@@ -1494,6 +1504,13 @@ func (m *Model) exportCallToLog(flow *sip.CallFlow, filename string) error {
 	fmt.Fprintf(f, "Transaction Flow:\n")
 	fmt.Fprintf(f, "-----------------\n")
 
+	// Calculate padding needed
+	digits := len(fmt.Sprintf("%d", len(flow.Packets)))
+	if digits < 2 {
+		digits = 2
+	}
+	numFmt := fmt.Sprintf("%%0%dd.", digits)
+
 	for i, pkt := range flow.Packets {
 		arrow := "->"
 		if len(flow.Packets) > 0 && pkt.SourceIP != flow.Packets[0].SourceIP {
@@ -1513,8 +1530,10 @@ func (m *Model) exportCallToLog(flow *sip.CallFlow, filename string) error {
 			dst = fmt.Sprintf("%s (%s)", dst, pkt.DestIP)
 		}
 
-		fmt.Fprintf(f, "%d. [%s] %s %s %s (%s line %d)\n",
-			i+1,
+		// Use pre-calculated format
+		numStr := fmt.Sprintf(numFmt, i+1)
+		fmt.Fprintf(f, "%s [%s] %s %s %s (%s line %d)\n",
+			numStr,
 			pkt.Timestamp.Format("15:04:05.000"),
 			src, arrow, dst,
 			summary,