fileExtension static method
Extracts the file extension from path.
Falls back to the canonical extension for fallbackType when the
path extension is unrecognised or absent.
Implementation
static String? fileExtension(
String path, {
required MessageType fallbackType,
}) {
final clean = path.split('?').first;
final parts = clean.split('.');
if (parts.length >= 2) {
final ext = parts.last.toLowerCase();
if (_extensionToPrefix.containsKey(ext)) return ext;
}
return _fallbackExtension(fallbackType);
}