chore: Add logging to agent_tool.py

Author: alexbond85

src/google/adk/tools/agent_tool.py

@@ -15,6 +15,7 @@
 from __future__ import annotations
 
 import inspect
+import logging
 from typing import Any
 from typing import Awaitable
 from typing import Callable
@@ -39,6 +40,8 @@
   from ..agents.base_agent import BaseAgent
   from ..events.event import Event
 
+logger = logging.getLogger('google_adk.' + __name__)
+
 
 class AgentTool(BaseTool):
   """A tool that wraps an agent.