gzipEncode function
Stub gzip implementation for platforms without dart:io (e.g., web).
Returns null since gzip is unavailable on these platforms.
Gzip-encodes the given bytes. Returns null on unsupported platforms.
Implementation
/// Gzip-encodes the given bytes. Returns `null` on unsupported platforms.
List<int>? gzipEncode(List<int> _) => null;