Refactor code structure for improved readability and maintainability

pyproject.toml

@@ -3,5 +3,47 @@ name = "backend"
 version = "0.1.0"
 description = "Add your description here"
 readme = "README.md"
-requires-python = ">=3.9"
-dependencies = []
+requires-python = ">=3.12"
+dependencies = [
+    # Web框架
+    "fastapi>=0.110.0",
+    "uvicorn>=0.27.0",
+    # LangGraph & LangChain
+    "langgraph>=0.0.40",
+    "langchain>=0.2.0",
+    "langchain-community>=0.2.0",
+    # DashScope
+    "dashscope>=1.14.0",
+    # Milvus
+    "pymilvus>=2.3.0",
+    # MinIO
+    "minio>=7.1.0",
+    # PostgreSQL
+    "sqlalchemy>=2.0.0",
+    "psycopg2-binary>=2.9.0",
+    # Redis (optional, for caching)
+    "redis>=5.0.0",
+    # 文档解析
+    "pypdf2>=3.0.0",
+    "python-docx>=1.1.0",
+    "pdfplumber>=0.10.0",
+    "pdf2image>=1.16.0",
+    "pillow>=11.3.0",
+    "pymupdf>=1.26.5",
+    "pytesseract>=0.3.13",
+    # Pydantic配置
+    "pydantic>=2.0.0",
+    "pydantic-settings>=2.0.0",
+    # 工具
+    "python-multipart>=0.0.9",
+    "sse-starlette>=1.8.0",
+    "python-dotenv>=1.0.0",
+    "tiktoken>=0.5.0",
+    "httpx>=0.25.0",
+]
+
+[dependency-groups]
+dev = [
+    "pytest>=7.4.0",
+    "pytest-asyncio>=0.21.0",
+]