feat: add default screen size detection and 960p screen size option (e.g. retroid pocket nova) (#1730)

* feat: add 960p default screen size (e.g. retroid pocket nova)

* feat: add default screen size detection

* use DisplayManager to get resolution from application context

* remove unused function createDefaultContainerFuture

* cache the default screen size to avoid detection every time

* use getRealMetrics

* fix mergeConfigurations when override screenSize is not the same as base.screenSize