fix: handle missing event loop in close() during interpreter shutdown

[haosenwang1018]

Closes #135

When the atexit handler calls close(), the default event loop policy may already be torn down during interpreter shutdown, causing asyncio.run() to raise RuntimeError: There is no current event loop in thread 'MainThread'.

This fix adds a fallback: if asyncio.run() fails, we manually create a new event loop with asyncio.new_event_loop() and run the finalization there. This ensures storages are properly finalized regardless of when the cleanup runs.