🐛 fix(process.py): add error handling for unknown langchain_object types

When processing the data graph, if the langchain_object is of an unknown type, a ValueError is now raised. This provides better error handling and helps identify any unexpected langchain_object types that may be encountered during processing.

src/backend/langflow/processing/process.py

@@ -107,6 +107,10 @@ def process_graph_cached(data_graph: Dict[str, Any], inputs: Optional[dict] = No
     elif isinstance(langchain_object, VectorStore):
         class_name = langchain_object.__class__.__name__
         result = {"message": f"Processed {class_name} successfully"}
+    else:
+        raise ValueError(
+            f"Unknown langchain_object type: {type(langchain_object).__name__}"
+        )
     return result