Add sys import to test files and remove obsolete integration tests

- Add sys import to 29 test files across agent-coordinator, blockchain-event-bridge, blockchain-node, and coordinator-api
- Remove apps/blockchain-event-bridge/tests/test_integration.py (obsolete bridge integration tests)
- Remove apps/coordinator-api/tests/test_integration.py (obsolete API integration tests)
- Implement GPU registration in marketplace_gpu.py with GPURegistry model persistence

apps/monitor/tests/test_unit_monitor.py

@@ -0,0 +1,108 @@
+"""Unit tests for monitor service"""
+
+import sys
+import pytest
+import sys
+from unittest.mock import Mock, patch, MagicMock, mock_open
+from pathlib import Path
+import json
+
+# Create a proper psutil mock with Error exception class
+class PsutilError(Exception):
+    pass
+
+mock_psutil = MagicMock()
+mock_psutil.cpu_percent = Mock(return_value=45.5)
+mock_psutil.virtual_memory = Mock(return_value=MagicMock(percent=60.2))
+mock_psutil.Error = PsutilError
+sys.modules['psutil'] = mock_psutil
+
+import monitor
+
+
+@pytest.mark.unit
+def test_main_system_stats_logging():
+    """Test that system stats are logged correctly"""
+    with patch('monitor.logging') as mock_logging, \
+         patch('monitor.time.sleep', side_effect=KeyboardInterrupt), \
+         patch('monitor.Path') as mock_path:
+        
+        mock_path.return_value.exists.return_value = False
+        
+        logger = mock_logging.getLogger.return_value
+        mock_logging.basicConfig.return_value = None
+        
+        try:
+            monitor.main()
+        except KeyboardInterrupt:
+            pass
+        
+        # Verify system stats were logged
+        assert logger.info.call_count >= 1
+        system_call = logger.info.call_args_list[0]
+        assert 'CPU 45.5%' in str(system_call)
+        assert 'Memory 60.2%' in str(system_call)
+
+
+@pytest.mark.unit
+def test_main_blockchain_stats_logging():
+    """Test that blockchain stats are logged when file exists"""
+    with patch('monitor.logging') as mock_logging, \
+         patch('monitor.time.sleep', side_effect=KeyboardInterrupt), \
+         patch('monitor.Path') as mock_path, \
+         patch('builtins.open', mock_open(read_data='{"blocks": [{"height": 1}, {"height": 2}]}')):
+        
+        # Mock blockchain file exists
+        blockchain_path = Mock()
+        blockchain_path.exists.return_value = True
+        marketplace_path = Mock()
+        marketplace_path.exists.return_value = False
+        
+        mock_path.side_effect = lambda x: blockchain_path if 'blockchain' in str(x) else marketplace_path
+        
+        logger = mock_logging.getLogger.return_value
+        mock_logging.basicConfig.return_value = None
+        
+        try:
+            monitor.main()
+        except KeyboardInterrupt:
+            pass
+        
+        # Verify blockchain stats were logged
+        blockchain_calls = [call for call in logger.info.call_args_list if 'Blockchain' in str(call)]
+        assert len(blockchain_calls) > 0
+        assert '2 blocks' in str(blockchain_calls[0])
+
+
+@pytest.mark.unit
+def test_main_marketplace_stats_logging():
+    """Test that marketplace stats are logged when file exists"""
+    with patch('monitor.logging') as mock_logging, \
+         patch('monitor.time.sleep', side_effect=KeyboardInterrupt), \
+         patch('monitor.Path') as mock_path, \
+         patch('builtins.open', mock_open(read_data='[{"id": 1, "gpu": "rtx3080"}, {"id": 2, "gpu": "rtx3090"}]')):
+        
+        # Mock blockchain file doesn't exist, marketplace does
+        blockchain_path = Mock()
+        blockchain_path.exists.return_value = False
+        marketplace_path = Mock()
+        marketplace_path.exists.return_value = True
+        listings_file = Mock()
+        listings_file.exists.return_value = True
+        listings_file.__truediv__ = Mock(return_value=listings_file)
+        marketplace_path.__truediv__ = Mock(return_value=listings_file)
+        
+        mock_path.side_effect = lambda x: listings_file if 'gpu_listings' in str(x) else (marketplace_path if 'marketplace' in str(x) else blockchain_path)
+        
+        logger = mock_logging.getLogger.return_value
+        mock_logging.basicConfig.return_value = None
+        
+        try:
+            monitor.main()
+        except KeyboardInterrupt:
+            pass
+        
+        # Verify marketplace stats were logged
+        marketplace_calls = [call for call in logger.info.call_args_list if 'Marketplace' in str(call)]
+        assert len(marketplace_calls) > 0
+        assert '2 GPU listings' in str(marketplace_calls[0])