Feat/assistant app (#2086)

Co-authored-by: chenhe <guchenhe@gmail.com>
Co-authored-by: Pascal M <11357019+perzeuss@users.noreply.github.com>

api/services/completion_service.py

@@ -227,6 +227,8 @@ class CompletionService:
             input_type = list(config.keys())[0]
 
             if variable not in user_inputs or not user_inputs[variable]:
+                if input_type == "external_data_tool":
+                    continue
                 if "required" in input_config and input_config["required"]:
                     raise ValueError(f"{variable} is required in input form")
                 else: