### Godot version

v4.1.1.stable.official [bd6af8e0e]

### System information

Godot v4.1.1.stable - Debian GNU/Linux trixie/sid trixie - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (nvidia) - Intel(R) Core(TM) i5-8400 CPU @ 2.80GHz (6 Threads)

### Issue description

`Area2D`s which extend beyond the bounds of the root viewport, eg. when using a `canvas_items` stretch mode, receive mouse input events even in the black bands letterboxing the game:

https://github.com/godotengine/godot/assets/441188/3beb962f-c1fa-4098-a375-f3d862013577


### Steps to reproduce

1. Set project stretch mode to either `canvas_items` or `viewport`
2. Have an `Area2D` whose `CollisionShape` extends beyond the bounds of the rendered region
3. Connect the `Area2D`'s `mouse_[entered|exited]` signal to something
4. Wave the mouse around in the black areas outside the rendered game

### Minimal reproduction project

Project used for video demo above:

[area2d-oob.zip](https://github.com/godotengine/godot/files/12207031/area2d-oob.zip)

This only demos `mouse_[entered|exited]`, but I first encountered this with the `Area2D.input_event` signal, where it received mouse clicks as well.
mb->set_position(pos);
			Control *mouse_focus = gui.mouse_focus;
			
			
			
			if (gui.mouse_focus_mask.is_empty()) {
				gui.mouse_focus = nullptr;
				gui.forced_mouse_focus = false;
			}
			bool stopped = mouse_focus && mouse_focus->can_process() && _gui_call_input(mouse_focus, mb);
			if (stopped) {
				set_input_as_handled();
			}
		}
	}
	Ref<InputEventMouseMotion> mm = p_event;
	if (mm.is_valid()) {
		gui.key_event_accepted = false;
		Point2 mpos = mm->get_position();
		
		if (!gui.drag_attempted && gui.mouse_focus && (mm->get_button_mask().has_flag(MouseButtonMask::LEFT))) {
			gui.drag_accum += mm->get_relative();
			float len = gui.drag_accum.length();
			if (len > 10) {
				{ 
					CanvasItem *ci = gui.mouse_focus;
					while (ci) {
						Control *control = Object::cast_to<Control>(ci);
						if (control) {
							gui.dragging = true;