truncate static method
Truncate text with ellipsis and bounds checking
Throws AssertionError if maxLength is negative. Returns empty string if maxLength is 0.
Example:
FSUtils.truncate('Very long text here', 10); // 'Very long...'
Implementation
static String truncate(String text, int maxLength) {
assert(maxLength >= 0, 'maxLength must be non-negative');
if (maxLength == 0) return '';
if (text.length <= maxLength) return text;
return '${text.substring(0, maxLength)}...';
}