Function insertion_text 

pub fn insertion_text(
    path: &str,
    line_range: Option<(usize, usize)>,
    line_mode: bool,
) -> String

Build the text to insert into the buffer when the user accepts a result.

• Normal: @path (trailing space so the user can continue typing).
• Line mode: @path:N-M when a range was parsed, else @path:.