Add capability to to fetch available screens and resolutions.

A nice feature to add
- List screens with supported resolutions.
- Select screen where the native window will be created.

On pure Java https://docs.oracle.com/en/java/javase/17/docs/api/java.desktop/java/awt/GraphicsEnvironment.html
On osx https://developer.apple.com/documentation/appkit/nsscreen

Start by reading the Java GraphicsEnvironment and macOS NSScreen references linked in the issue, then locate Korge's native window creation entry points for its supported targets. Define how screens, resolutions, and the selected screen should be exposed across platforms; done means callers can list available displays and create the native window on the selected one.

Written by the indexing model from the issue text.