remove top level retriver model

backend/semantic_search.py

@@ -11,7 +11,7 @@ VECTOR_COLUMN = os.getenv("VECTOR_COLUMN", "vector")
 TEXT_COLUMN = os.getenv("TEXT_COLUMN", "text")
 BATCH_SIZE = int(os.getenv("BATCH_SIZE", 32))
 
-retriever = SentenceTransformer(os.getenv("EMB_MODEL"))
+#retriever = SentenceTransformer(os.getenv("EMB_MODEL"))
 
 
 def retrieve(query, k, table_name, embedding_model_name):