Game code uses standard Python file I/O to mcrfpy.save_dir with no platform
branching. On WASM, builtins.open() is monkeypatched so writes to /save/
auto-sync IDBFS on close, making persistence transparent.
API: mcrfpy.save_dir (str), mcrfpy._sync_storage() (auto-called on WASM)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>