Fix langchain imports: use langchain.memory for ConversationBufferWindowMemory, use langchain_core.tools for BaseTool (langchain 0.3.27 compatibility)

src/agent/memory_manager.py

@@ -1,4 +1,4 @@
-from langchain_community.memory import ConversationBufferWindowMemory
+from langchain.memory import ConversationBufferWindowMemory
 from typing import Dict, Any, List, Optional
 
 class MemoryManager:

src/agent/research_agent.py

@@ -1,6 +1,6 @@
 from langchain_google_genai import ChatGoogleGenerativeAI
 from langchain_community.llms import Ollama
-from langchain_community.memory import ConversationBufferWindowMemory
+from langchain.memory import ConversationBufferWindowMemory
 from typing import List, Dict, Any
 import asyncio
 from datetime import datetime

src/tools/base_tool.py

@@ -1,6 +1,6 @@
 from abc import ABC, abstractmethod
 from typing import Dict, Any, Optional, Union
-from langchain_community.tools import BaseTool
+from langchain_core.tools import BaseTool
 from pydantic import BaseModel, Field, PrivateAttr, field_validator
 import asyncio
 import aiohttp

src/tools/chart_creator_tool.py

@@ -1,4 +1,4 @@
-from langchain_community.tools import BaseTool
+from langchain_core.tools import BaseTool
 from pydantic import BaseModel, Field
 from typing import Dict, Any, List, Optional
 import json

src/tools/chart_data_tool.py

@@ -1,4 +1,4 @@
-from langchain_community.tools import BaseTool
+from langchain_core.tools import BaseTool
 from pydantic import BaseModel, Field
 from typing import Dict, Any, List, Optional
 import json