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/agent-services/agent-registry/tests/test_unit_agent_registry.py

@@ -0,0 +1,105 @@
+"""Unit tests for agent registry service"""
+
+import pytest
+import sys
+import sys
+from pathlib import Path
+
+
+from app import app, Agent, AgentRegistration
+
+
+@pytest.mark.unit
+def test_app_initialization():
+    """Test that the FastAPI app initializes correctly"""
+    assert app is not None
+    assert app.title == "AITBC Agent Registry API"
+    assert app.version == "1.0.0"
+
+
+@pytest.mark.unit
+def test_agent_model():
+    """Test Agent model"""
+    agent = Agent(
+        id="agent_123",
+        name="Test Agent",
+        type="trading",
+        capabilities=["trading", "analysis"],
+        chain_id="ait-devnet",
+        endpoint="http://localhost:8000",
+        metadata={"region": "us-east"}
+    )
+    assert agent.id == "agent_123"
+    assert agent.name == "Test Agent"
+    assert agent.type == "trading"
+    assert agent.capabilities == ["trading", "analysis"]
+
+
+@pytest.mark.unit
+def test_agent_model_empty_capabilities():
+    """Test Agent model with empty capabilities"""
+    agent = Agent(
+        id="agent_123",
+        name="Test Agent",
+        type="trading",
+        capabilities=[],
+        chain_id="ait-devnet",
+        endpoint="http://localhost:8000"
+    )
+    assert agent.capabilities == []
+
+
+@pytest.mark.unit
+def test_agent_model_no_metadata():
+    """Test Agent model with default metadata"""
+    agent = Agent(
+        id="agent_123",
+        name="Test Agent",
+        type="trading",
+        capabilities=["trading"],
+        chain_id="ait-devnet",
+        endpoint="http://localhost:8000"
+    )
+    assert agent.metadata == {}
+
+
+@pytest.mark.unit
+def test_agent_registration_model():
+    """Test AgentRegistration model"""
+    registration = AgentRegistration(
+        name="Test Agent",
+        type="trading",
+        capabilities=["trading", "analysis"],
+        chain_id="ait-devnet",
+        endpoint="http://localhost:8000",
+        metadata={"region": "us-east"}
+    )
+    assert registration.name == "Test Agent"
+    assert registration.type == "trading"
+    assert registration.capabilities == ["trading", "analysis"]
+
+
+@pytest.mark.unit
+def test_agent_registration_model_empty_capabilities():
+    """Test AgentRegistration with empty capabilities"""
+    registration = AgentRegistration(
+        name="Test Agent",
+        type="trading",
+        capabilities=[],
+        chain_id="ait-devnet",
+        endpoint="http://localhost:8000"
+    )
+    assert registration.capabilities == []
+
+
+@pytest.mark.unit
+def test_agent_registration_model_no_metadata():
+    """Test AgentRegistration with default metadata"""
+    registration = AgentRegistration(
+        name="Test Agent",
+        type="trading",
+        capabilities=["trading"],
+        chain_id="ait-devnet",
+        endpoint="http://localhost:8000"
+    )
+    assert registration.metadata == {}