Description
parseListItem does not recognize a leading '>' so checkboxes inside Obsidian callouts (> [!Tasks]) never toggle. Teach parseListItem an optional blockquote prefix (one or more '>' each optionally followed by a space); Alt+x and mouse click both inherit it via parseListItem.
Acceptance Criteria
- #1 Alt+x toggles a '> - [ ] x' checkbox line
- #2 Mouse click on the box glyph inside a callout toggles it
- #3 List continuation preserves the '> ' prefix