pub fn trailing_blank_line_count(lines: &[&str], start: usize, end: usize) -> usize {
if start >= end || start >= lines.len() {
return 0;
}
let upper = end.min(lines.len());
let mut count = 0usize;
for idx in (start..upper).rev() {
if lines[idx].trim().is_empty() {
count += 1;
} else {
break;
}
}
count
}