Update requirements.txt

requirements.txt

@@ -1,17 +1,18 @@
-# ─── UI & 服务 ───
 gradio==4.44.1
 uvicorn[standard]
 
-# ─── LLM & 向量库相关 ───
-transformers==4.38.0
-torch==2.2.0
-accelerate==0.27.2
-chromadb==0.4.24
-sentence-transformers==2.7.0
+transformers>=4.38.0
+torch>=2.2.0
+accelerate>=0.27.2
+
+chromadb>=0.4.24
+sentence-transformers>=2.7.0
+
+langchain>=0.2.0
+langchain-community>=0.0.40
+langchain-huggingface
+langchain-chroma
+unstructured  # 如果你在 Space 上执行 build_index.py
 
-# ─── LangChain 生态 ───
-langchain==0.1.13
-langchain-community==0.0.29
-langchain-chroma==0.1.0