sanitizeFileName function
Implementation
String sanitizeFileName(String input, {String fallback = 'video'}) {
final trimmed = input.trim();
if (trimmed.isEmpty) return fallback;
final replaced = trimmed
.replaceAll(RegExp(r'[\\/:*?"<>|\x00-\x1F]'), '_')
.replaceAll(RegExp(r'\s+'), ' ')
.trim();
if (replaced.isEmpty) return fallback;
return replaced.length > 120 ? replaced.substring(0, 120) : replaced;
}