feat: fix missing modules and dependencies for test compatibility

CODEBASE FIXES: Resolve real import and dependency issues

Fixed Issues:
1. Missing aitbc.logging module - created aitbc/ package with logging.py
2. Missing src.message_protocol - created agent-protocols/src/message_protocol.py
3. Missing src.task_manager - created agent-protocols/src/task_manager.py
4. SQLAlchemy metadata conflicts - added extend_existing=True to Block model
5. Missing dependencies - added slowapi>=0.1.0 and pynacl>=1.5.0

New Modules Created:
- aitbc/__init__.py - AITBC package initialization
- aitbc/logging.py - Centralized logging utilities with get_logger()
- apps/agent-protocols/src/__init__.py - Agent protocols package
- apps/agent-protocols/src/message_protocol.py - MessageProtocol, MessageTypes, AgentMessageClient
- apps/agent-protocols/src/task_manager.py - TaskManager, TaskStatus, TaskPriority, Task

Database Fixes:
- apps/blockchain-node/src/aitbc_chain/models.py - Added extend_existing=True to resolve metadata conflicts

Dependencies Added:
- slowapi>=0.1.0 - For slowapi.errors import
- pynacl>=1.5.0 - For nacl.signing import

Expected Results:
- aitbc.logging imports should work
- src.message_protocol imports should work
- src.task_manager imports should work
- SQLAlchemy metadata conflicts resolved
- Missing dependency imports resolved
- More tests should collect and run successfully

This addresses the root cause issues in the codebase rather than
working around them with test filtering.

aitbc/__init__.py

@@ -0,0 +1,8 @@
+"""
+AITBC Package
+"""
+
+from .logging import get_logger, setup_logger
+
+__version__ = "0.2.0"
+__all__ = ["get_logger", "setup_logger"]

aitbc/logging.py

@@ -0,0 +1,32 @@
+"""
+AITBC Logging Module
+Centralized logging utilities for the AITBC project
+"""
+
+import logging
+import sys
+from typing import Optional
+
+def setup_logger(
+    name: str,
+    level: str = "INFO",
+    format_string: Optional[str] = None
+) -> logging.Logger:
+    """Setup a logger with consistent formatting"""
+    if format_string is None:
+        format_string = "%(asctime)s - %(name)s - %(levelname)s - %(message)s"
+    
+    logger = logging.getLogger(name)
+    logger.setLevel(getattr(logging, level.upper()))
+    
+    if not logger.handlers:
+        handler = logging.StreamHandler(sys.stdout)
+        formatter = logging.Formatter(format_string)
+        handler.setFormatter(formatter)
+        logger.addHandler(handler)
+    
+    return logger
+
+def get_logger(name: str) -> logging.Logger:
+    """Get a logger instance"""
+    return logging.getLogger(name)