Function render_to_string 

pub fn render_to_string(markdown: &str, width: usize) -> String

Render a markdown string to a single String with ANSI styling.

This is a stateless convenience function that parses the input, renders each element, and joins with \n. For incremental rendering with terminal cursor control, use Markdown::render or StreamRenderer.

Always uses ThemeMode::Auto and no custom code theme.