Handle low memory event

[Alex2772]

Describe the need of your project

Modern OSes provide a way to handle high memory pressure. We'd like to handle such event. Also, it would be useful if AUI would print this signal emission to logs by default. AUI has several caches for textures, sounds, etc... so they can subscribe to this signal as well.

Proposed solution

Make global AObject like ASharedApplication with signal lowMemoryNotified. The underlying implementations:

• Windows: CreateMemoryResourceNotification
• Linux: /sys/fs/cgroup/memory/memory.pressure_level fd
• macOS: simulating low memory condition
• Android: onTrimMemory, onLowMemory
• iOS: UIKit didReceiveMemoryWarning

Alternatives you've considered

No response

Additional context

No response