Fix stats display in test_monitor_tshark.sh

- Filter out 'X packets captured' summary lines from packet count
- Only count lines with tab-separated fields (actual packet data)
- Add sync to force output flush
- Ensure stats always display immediately after capture
- Remove trap that was interfering with normal flow

Co-authored-by: Cursor <cursoragent@cursor.com>

test_monitor_tshark.sh

@@ -119,7 +119,7 @@ echo ""
 # Capture for specified duration and count packets
 echo "Capturing packets for $DURATION seconds..."
 
-# Run capture in background and show progress
+# Run capture with timeout
 CAPTURE_OUTPUT=$(timeout "$DURATION" tshark -i "$INTERFACE" -n -T fields \
     -e frame.number \
     -e frame.time \
@@ -132,25 +132,30 @@ CAPTURE_OUTPUT=$(timeout "$DURATION" tshark -i "$INTERFACE" -n -T fields \
     2>&1)
 CAPTURE_EXIT_CODE=$?
 
-# Immediately show stats after capture completes
+# Force output flush
+sync
+
+# Show stats immediately after capture completes
 echo ""
 echo "=== Capture Statistics ==="
 
-# Show any warnings/errors
-WARNINGS=$(echo "$CAPTURE_OUTPUT" | grep -E "(tshark:|Warning|Error)" | head -5 || true)
+# Show any warnings/errors (but not the "Running as root" or "Capturing" messages)
+WARNINGS=$(echo "$CAPTURE_OUTPUT" | grep -E "(tshark:|Warning|Error)" | grep -v -E "(Running as|Capturing)" | head -5 || true)
 if [ -n "$WARNINGS" ]; then
     echo "$WARNINGS"
+    echo ""
 fi
 
-# Count total packets captured (lines starting with a number)
-PACKET_LINES=$(echo "$CAPTURE_OUTPUT" | grep -E '^[0-9]+' || true)
+# Count total packets captured (lines starting with a number followed by tab)
+# Filter out lines like "100 packets captured" which don't have tabs
+PACKET_LINES=$(echo "$CAPTURE_OUTPUT" | grep -E '^[0-9]+\t' || true)
 FINAL_COUNT=$(echo "$PACKET_LINES" | wc -l || echo "0")
 
 # Count packets with PLCP headers (radiotap present)
 # radiotap.present field is the 8th field (after frame.number, frame.time, wlan.sa, wlan.da, wlan.fc.type, wlan.fc.subtype, wlan.fc.type_subtype)
 PLCP_COUNT=$(echo "$PACKET_LINES" | awk -F'\t' 'NF >= 8 && $1 != "" && $8 != "" && $8 != "0" && $8 != "-" {count++} END {print count+0}' || echo "0")
 
-# Display stats immediately
+# Display stats immediately - always show these
 echo "Total packets captured: $FINAL_COUNT"
 echo "PLCP headers: $PLCP_COUNT"
 if [ "$FINAL_COUNT" -gt 0 ]; then