One item of a ListBlock: blocks (paragraphs, images, nested lists) laid out beside one marker.
public sealed class ListItem
ISO 32000-2 §14.8.4.8.2: tagged as LI holding the marker as Lbl and the blocks in LBody.
kind:method, kind:property, kind:ctor. Press Esc to clear.ListItem(IEnumerable<FlowBlock>)Creates an item holding blocks.ListItem(String, ParagraphStyle)Creates an item holding one paragraph.