### 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.
ERR_MAIN_THREAD_GUARD_V(nullptr);
	
	_gui_sort_roots();
	for (List<Control *>::Element *E = gui.roots.back(); E; E = E->prev()) {
		Control *sw = E->get();
		if (!sw->is_visible_in_tree()) {
			continue;
		}
		Transform2D xform;
		CanvasItem *pci = sw->get_parent_item();
		if (pci) {
			xform = pci->get_global_transform_with_canvas();
		} else {
			xform = sw->get_canvas_transform();
		}
		Control *ret = _gui_find_control_at_pos(sw, p_global, xform);
		if (ret) {
			return ret;
		}
	}
	return nullptr;
}
Control *Viewport::_gui_find_control_at_pos(CanvasItem *p_node, const Point2 &p_global, const Transform2D &p_xform) {