feat: 1. replace black with ruff for fomatting and sort import (#489)

2. use tavily from`langchain-tavily` rather than the older one from `langchain-community`

Co-authored-by: Willem Jiang <willem.jiang@gmail.com>

tests/unit/rag/test_ragflow.py

@@ -1,8 +1,10 @@
 # Copyright (c) 2025 Bytedance Ltd. and/or its affiliates
 # SPDX-License-Identifier: MIT
 
+from unittest.mock import MagicMock, patch
+
 import pytest
-from unittest.mock import patch, MagicMock
+
 from src.rag.ragflow import RAGFlowProvider, parse_uri
 
 

tests/unit/rag/test_retriever.py

@@ -2,6 +2,7 @@
 # SPDX-License-Identifier: MIT
 
 import pytest
+
 from src.rag.retriever import Chunk, Document, Resource, Retriever
 
 

tests/unit/rag/test_vikingdb_knowledge_base.py

@@ -1,13 +1,15 @@
 # Copyright (c) 2025 Bytedance Ltd. and/or its affiliates
 # SPDX-License-Identifier: MIT
 
-import os
-import pytest
-import json
 import hashlib
 import hmac
-from unittest.mock import patch, MagicMock
+import json
+import os
 from datetime import datetime
+from unittest.mock import MagicMock, patch
+
+import pytest
+
 from src.rag.vikingdb_knowledge_base import VikingDBKnowledgeBaseProvider, parse_uri