How to get distinct x number of threads with metadata filtering

[Hiraveb]

How to get distinct x number of threads with metadata filtering, so ai agent can show all threads in the sidebar

since mongodb checkpointer updated, on how metadata stored, this migration created some breaking changes. do we have any interface which can handle both of these type of docs

        old_format_match = {
            "metadata.user_id": user_id_binary,
            "metadata.assistant_id": assistant_id_binary,
        }

        new_format_match = {
            "metadata.user_id": {"$type": "array"},
            "metadata.assistant_id": {"$type": "array"},
        }