feat: Add OSINT features (v0.1.2)

- MAC vendor lookup (IEEE OUI database)
- BLE company_id to manufacturer mapping
- Device profile enrichment in API responses
- Export endpoints: devices.csv, devices.json, alerts.csv, probes.csv
- Auto-populate vendor on device creation
- CLI command: flask download-oui
- Makefile target: make oui

13 tests passing

tests/test_api/test_sensors.py

@@ -18,4 +18,6 @@ def test_health_check(client):
     """Test health endpoint."""
     response = client.get('/health')
     assert response.status_code == 200
-    assert response.json == {'status': 'ok'}
+    assert response.json['status'] == 'ok'
+    assert 'uptime' in response.json
+    assert 'uptime_seconds' in response.json