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/global-infrastructure/tests/test_unit_global_infrastructure.py

@@ -0,0 +1,93 @@
+"""Unit tests for global infrastructure service"""
+
+import pytest
+import sys
+import sys
+from pathlib import Path
+from datetime import datetime
+
+
+from main import app, Region, GlobalDeployment, LoadBalancer, PerformanceMetrics
+
+
+@pytest.mark.unit
+def test_app_initialization():
+    """Test that the FastAPI app initializes correctly"""
+    assert app is not None
+    assert app.title == "AITBC Global Infrastructure Service"
+    assert app.version == "1.0.0"
+
+
+@pytest.mark.unit
+def test_region_model():
+    """Test Region model"""
+    region = Region(
+        region_id="us-east-1",
+        name="US East",
+        location="North America",
+        endpoint="https://us-east-1.api.aitbc.dev",
+        status="active",
+        capacity=10000,
+        current_load=3500,
+        latency_ms=45,
+        compliance_level="full"
+    )
+    assert region.region_id == "us-east-1"
+    assert region.name == "US East"
+    assert region.status == "active"
+    assert region.capacity == 10000
+    assert region.compliance_level == "full"
+
+
+@pytest.mark.unit
+def test_global_deployment_model():
+    """Test GlobalDeployment model"""
+    deployment = GlobalDeployment(
+        deployment_id="deploy_123",
+        service_name="test-service",
+        target_regions=["us-east-1", "eu-west-1"],
+        configuration={"replicas": 3},
+        deployment_strategy="blue_green",
+        health_checks=["/health", "/ready"]
+    )
+    assert deployment.deployment_id == "deploy_123"
+    assert deployment.service_name == "test-service"
+    assert deployment.target_regions == ["us-east-1", "eu-west-1"]
+    assert deployment.deployment_strategy == "blue_green"
+
+
+@pytest.mark.unit
+def test_load_balancer_model():
+    """Test LoadBalancer model"""
+    balancer = LoadBalancer(
+        balancer_id="lb_123",
+        name="Main LB",
+        algorithm="round_robin",
+        target_regions=["us-east-1", "eu-west-1"],
+        health_check_interval=30,
+        failover_threshold=3
+    )
+    assert balancer.balancer_id == "lb_123"
+    assert balancer.name == "Main LB"
+    assert balancer.algorithm == "round_robin"
+    assert balancer.health_check_interval == 30
+
+
+@pytest.mark.unit
+def test_performance_metrics_model():
+    """Test PerformanceMetrics model"""
+    metrics = PerformanceMetrics(
+        region_id="us-east-1",
+        timestamp=datetime.utcnow(),
+        cpu_usage=50.5,
+        memory_usage=60.2,
+        network_io=1000.5,
+        disk_io=500.3,
+        active_connections=100,
+        response_time_ms=45.2
+    )
+    assert metrics.region_id == "us-east-1"
+    assert metrics.cpu_usage == 50.5
+    assert metrics.memory_usage == 60.2
+    assert metrics.active_connections == 100
+    assert metrics.response_time_ms == 45.2