Type name, prefixed with @ to signal that this is a toolkit-specific node.
Unique key for this list (within its parent)
List mode, signaling that list nodes can appear as direct children
Level/depth of this list node (starts at 1)
Style of this list item (bullet, number are common values, but can be customized)
Child nodes of this list - either portable text list items, or another, deeper list
Toolkit-specific type representing a nested list in "direct" mode, where deeper lists are nested inside of the lists children, alongside other blocks.