Add "New Window" option to Handle Menu.

Adds the "New Window" option to Handle Menu when the task that opened
Handle Menu supports multi-instance. The button will do the following:

1 - In a fullscreen task, opens the calling task and a new instance in
split screen.
2 - In a split screen task, replaces the non-calling task with a new
instance of the calling task.
3 - In a desktop task, opens a new instance in a desktop window.

Still to implement: Launched freeform apps do not currently respect the
desktop windowing limit. Additionally, we still need a transition
handler to ensure animations match the spec.

Bug: 336289597
Test: Manual, atest desktop tests
Flag: com.android.window.flags.enable_desktop_windowing_multi_instance_features

Change-Id: I5b3bde3e00ebbe014870237108ccbeb658b73d7c