### 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_READ_THREAD_GUARD_V(false);
	return physics_object_picking;
}
void Viewport::set_physics_object_picking_sort(bool p_enable) {
	ERR_MAIN_THREAD_GUARD;
	physics_object_picking_sort = p_enable;
}
bool Viewport::get_physics_object_picking_sort() {
	ERR_READ_THREAD_GUARD_V(false);
	return physics_object_picking_sort;
}
Vector2 Viewport::get_camera_coords(const Vector2 &p_viewport_coords) const {
	ERR_READ_THREAD_GUARD_V(Vector2());
	Transform2D xf = stretch_transform * global_canvas_transform;
	return xf.xform(p_viewport_coords);
}
Vector2 Viewport::get_camera_rect_size() const {
	ERR_READ_THREAD_GUARD_V(Vector2());
	return size;
}
void Viewport::set_disable_input(bool p_disable) {