Add waitable swapchain

[darksylinc]

• Production edit: Related to [RFC] D3D12: Use waitable swap chain to reduce input latency #94960.

[Calinou]

Suggested change

	Instructs Godot to use Waitable Swapchains when supported. Normally Godot allows the GPU to get [member rendering/rendering_device/vsync/frame_queue_size] ahead of the GPU. Assuming frame_queue_size = 2, Godot normally starts working on frame N+2 with the CPU when the GPU is done working on frame N. This setting makes Godot start frame N+2 when frame N is [i]done presenting[/i].
	This gap between when the GPU finishes its work and when that work actually appears on screen can increase latency. [b]Enabling this setting thus reduces latency[/b] at the cost of some framerate (framerate may decrease because the CPU has to wait more time doing nothing).
	Instructs Godot to use Waitable Swapchains when supported. Normally, Godot allows the GPU to get [member rendering/rendering_device/vsync/frame_queue_size] ahead of the GPU. Assuming [code]frame_queue_size = 2[/code], Godot normally starts working on frame [code]N + 2[/code] with the CPU when the GPU is done working on frame [code]N[/code]. This setting makes Godot start frame [code]N + 2[/code] when frame [code]N[/code] is [i]done presenting[/i].
	This gap between when the GPU finishes its work and when that work actually appears on screen can increase latency. [b]Enabling this setting thus reduces latency[/b] at the cost of some framerate (framerate may decrease because the CPU has to wait more time doing nothing).

[darksylinc]

Superseeded by #106221