Function render_task_decomposition_block 

pub fn render_task_decomposition_block(
    rows: &[TaskRow],
) -> Result<String, RenderError>

Render the task-decomposition table block (header row, separator row, and one row per rows entry) through the nils_markdown::Engine. Output is byte-equal to the previous concatenation of [task_decomposition_header_row], [task_decomposition_separator_row], and format_task_decomposition_row for the same rows.