refactor: migrate all remaining modules to use shared aitbc.logging from aitbc-core package

- Replace `import logging` with `from aitbc.logging import get_logger` across blockchain-node scripts and coordinator-api modules
- Update logger initialization from `logging.getLogger(__name__)` to `get_logger(__name__)` in 30+ files
- Add production configuration validators for API keys, HMAC secret, and JWT secret in coordinator config
- Enhance coordinator startup with comprehensive initialization logging

apps/coordinator-api/scripts/phase5_implementation.py

@@ -5,12 +5,12 @@ Week 9-12: Enterprise scaling and agent marketplace development
 
 import asyncio
 import json
-import logging
+from aitbc.logging import get_logger
 from datetime import datetime
 from typing import Dict, List, Optional, Any
 from enum import Enum
 
-logger = logging.getLogger(__name__)
+logger = get_logger(__name__)
 
 
 class Phase5Implementation: