added Hybrid Search with BM25

app.py

@@ -270,7 +270,7 @@ class BSIChatbot:
         all_documents = []
 
         # Iteriere über alle IDs im index_to_docstore_id
-        for doc_id in vector_store.index_to_docstore_id.values():
+        for doc_id in vectorstore.index_to_docstore_id.values():
             # Hole das Dokument aus dem docstore
             document = vector_store.docstore[doc_id]
             all_documents.append(document)