feat: add metadata

custom_pgvector.py

@@ -353,7 +353,11 @@ class CustomPGVector(VectorStore):
             (
                 Document(
                     page_content=result.Article.abstract,
-                    # metadata={"title": result.Article.title},
+                    metadata={
+                        "id": result.Article.id,
+                        "title": result.Article.title,
+                        "doi": result.Article.doi
+                    },
                 ),
                 result.distance if self.embedding_function is not None else None,
             )