Migrate CLI and Python packages to centralized aitbc package utilities

CLI migration:
- Migrate 11 CLI files from old import pattern to centralized aitbc imports
- wallet.py, exchange.py, gpu_marketplace.py, exchange_island.py, monitor.py, cross_chain.py
- aitbc_cli.py, handlers (account.py, bridge.py, pool_hub.py), utils (wallet_daemon_client.py)
- Replace 'from aitbc.aitbc_logging import' with 'from aitbc import get_logger'
- Replace 'from aitbc.http_client import' with 'from aitbc import AITBCHTTPClient'
- Replace 'from aitbc.exceptions import' with 'from aitbc import NetworkError'

Packages migration:
- aitbc-sdk: receipts.py - migrate from httpx to AITBCHTTPClient
- aitbc-agent-sdk: 5 files - migrate logging to get_logger
  - agent.py, compute_provider.py, compute_consumer.py, swarm_coordinator.py, platform_builder.py

packages/py/aitbc-agent-sdk/src/aitbc_agent/platform_builder.py

@@ -2,14 +2,15 @@
 Platform Builder - factory for constructing AITBC agent platform configurations
 """
 
-import logging
 from typing import Dict, List, Any, Optional
 from .agent import Agent, AgentCapabilities, AgentIdentity
 from .compute_provider import ComputeProvider
 from .compute_consumer import ComputeConsumer
 from .swarm_coordinator import SwarmCoordinator
 
-logger = logging.getLogger(__name__)
+from aitbc import get_logger
+
+logger = get_logger(__name__)
 
 
 class PlatformBuilder: