Enhance Dockerfile to include tcpdump for network monitoring

lib/services/protocol_blocking_service.dart

@@ -34,27 +34,48 @@ class ProtocolBlockingService {
   }
   
   static void _startConnectionMonitoring() {
+    print('📡 Starting connection monitoring timer (100ms intervals)...');
     _monitorTimer = Timer.periodic(Duration(milliseconds: 100), (_) async {
       await _scanForNewConnections();
     });
   }
   
   static Future<void> _scanForNewConnections() async {
+    static int scanCount = 0;
+    scanCount++;
+    
     try {
       // Monitor both TCP and UDP connections
       final tcpResult = await Process.run('ss', ['-tnp', 'state', 'syn-sent,established']);
       final udpResult = await Process.run('ss', ['-unp']);
       
+      if (scanCount % 100 == 0) { // Log every 10 seconds
+        print('🔍 Scan #$scanCount - TCP exit code: ${tcpResult.exitCode}, UDP exit code: ${udpResult.exitCode}');
+      }
+      
+      if (tcpResult.exitCode != 0) {
+        print('❌ TCP ss command failed: ${tcpResult.stderr}');
+        return;
+      }
+      if (udpResult.exitCode != 0) {
+        print('❌ UDP ss command failed: ${udpResult.stderr}');
+        return;
+      }
+      
       final tcpConnections = _parseConnections(tcpResult.stdout.toString(), 'tcp');
       final udpConnections = _parseConnections(udpResult.stdout.toString(), 'udp');
       
+      if (scanCount % 100 == 0) {
+        print('🔍 Found ${tcpConnections.length} TCP + ${udpConnections.length} UDP connections');
+      }
+      
       for (final conn in [...tcpConnections, ...udpConnections]) {
         if (_isNewConnection(conn)) {
           await _handleNewConnection(conn);
         }
       }
     } catch (e) {
-      print('Error scanning for connections: $e');
+      print('❌ Error scanning for connections: $e');
     }
   }