Add blockchain event bridge service with smart contract event integration

- Phase 1: Core bridge service with gossip broker subscription
- Phase 2: Smart contract event integration via eth_getLogs RPC endpoint
- Add contract event subscriber for AgentStaking, PerformanceVerifier, Marketplace, Bounty, CrossChainBridge
- Add contract event handlers in agent_daemon.py and marketplace.py
- Add systemd service file for blockchain-event-bridge
- Update blockchain node router.py with eth_getLogs endpoint
- Add configuration for contract addresses
- Add tests for contract subscriber and handlers (27 tests passing)

apps/blockchain-event-bridge/pytest.ini

@@ -0,0 +1,29 @@
+[pytest]
+# pytest configuration for blockchain-event-bridge
+
+# Test discovery
+python_files = test_*.py
+python_classes = Test*
+python_functions = test_*
+
+# Custom markers
+markers =
+    unit: Unit tests (fast, isolated)
+    integration: Integration tests (may require external services)
+    slow: Slow running tests
+
+# Additional options
+addopts =
+    --verbose
+    --tb=short
+
+# Python path for imports
+pythonpath =
+    .
+    src
+
+# Warnings
+filterwarnings =
+    ignore::UserWarning
+    ignore::DeprecationWarning
+    ignore::PendingDeprecationWarning