重排，多路查询

rag_core/__init__.py

@@ -7,6 +7,8 @@ RAG Core - 公共 RAG 组件包
 from .embedders import LlamaCppEmbedder
 from .vector_store import QdrantVectorStore, QDRANT_URL, QDRANT_API_KEY
 from .store import PostgresDocStore, create_docstore
+from .retriever_factory import create_parent_retriever
+
 
 __all__ = [
     "LlamaCppEmbedder",
@@ -15,4 +17,5 @@ __all__ = [
     "QDRANT_API_KEY",
     "PostgresDocStore",
     "create_docstore",
+    "create_parent_retriever",
 ]