Output format: Is 'data' always included as the empty object?

For a valid delimiter block, is the `data` property always included as the empty object, or can it under any circumstances (now or in the future) be `null` or omitted?

Context: I'm a back-end .NET developer needing to parse Editor.js documents. The readme says that "This tool returns empty object", but I'd just like clarification on whether that means it will always (now and in the future) be included and non-`null`.

Read the README section describing the delimiter block output and inspect the valid block's serialized data shape. Confirm whether the data property is guaranteed to be present and non-null, then document that behavior and its future expectations in the README.

Written by the indexing model from the issue text.