mdz_stream_parser_list.ts

List handlers for the streaming mdz parser — column-0 list starts and the line classifier that drives structure inside open lists.

The streaming analogue of the sync lexer's #tokenize_list: the level stack lives in state.list_levels, and List/ListItem frames sit on the main stack (never reverted, like Paragraph). Every line inside an open list classifies from bounded input — leading whitespace plus a few marker chars for most lines, the whole line for empty markers and fence openers — and blank-run containment consumes one blank line at a time, holding only the structural close-vs-contain decision, never renderable content.