fileSize method
Returns the size of the file at the specified path.
Implementation
@override
Future<int> fileSize(String path) async {
final file =
await getFile(path); // getFile already resolves and handles root
if (!await file.exists()) {
throw FileSystemException(
"File not found for size check: $path (resolved to ${file.path})");
}
return await file.length();
}