feat: 实现 BM25 稀疏 + 稠密向量混合检索功能

backend/requirements.txt

@@ -1,53 +1,52 @@
-# Core
-pydantic==2.12.5
-python-dotenv==1.2.2
-typing-extensions==4.15.0
+typing-extensions>=4.15.0
+python-dotenv>=1.2.2
+pydantic>=2.12.5
+requests>=2.32.5
 
 # LangChain
-langchain==1.2.15
-langchain-community==0.4.1
-langchain-core==1.2.28
-langchain-openai==1.1.12
-langchain-qdrant==1.1.0
-langgraph==1.1.6
-langgraph-checkpoint-postgres==3.0.5
+langchain>=1.2.15
+langchain-community>=0.4.1
+langchain-core>=1.2.28
+langchain-openai>=1.1.12
+langchain-qdrant>=1.1.0
+langgraph>=1.1.6
+langgraph-checkpoint-postgres>=3.0.5
 tiktoken>=0.12.0
 
 # Zhipu AI
-zhipuai==2.0.1
+zhipuai>=2.0.1
 
 # Vector DB
-qdrant-client==1.17.1
+qdrant-client>=1.17.1
 fastembed>=0.3.0  # 用于 Qdrant BM25 稀疏向量
 
 # Memory
-mem0ai==1.0.11
+mem0ai>=1.0.11
 
 # Backend
-fastapi==0.135.3
-uvicorn[standard]==0.44.0
+fastapi>=0.135.3
+uvicorn[standard]>=0.44.0
 
 # Database
-asyncpg==0.31.0
-psycopg[binary]==3.3.3
+asyncpg>=0.31.0
+psycopg[binary]>=3.3.3
 
 # HTTP
-httpx==0.28.1
-aiohttp==3.13.5
+httpx>=0.28.1
+aiohttp>=3.13.5
 
 # Utilities
-tenacity==9.1.4
-rich==15.0.0
-PyYAML==6.0.3
+tenacity>=9.1.4
+rich>=15.0.0
+PyYAML>=6.0.3
 numpy>=1.26.2
-pyjwt==2.8.0
+pyjwt>=2.8.0
 ddgs>=6.0.0              # 免费联网搜索（原 duckduckgo-search 已重命名）
 matplotlib>=3.9.0         # 可视化图表
 
 # Document Processing
-unstructured==0.22.21
-pypdf==6.10.0
-beautifulsoup4==4.14.3
-lxml==6.1.0
-pandas==3.0.2        # 若需Excel保留，否则移除
-spacy==3.8.14         # unstructured 可能依赖
+unstructured>=0.22.21
+pypdf>=6.10.0
+beautifulsoup4>=4.14.3
+lxml>=6.1.0
+spacy>=3.8.14         # unstructured 可能依赖