### 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(Transform2D());
	return canvas_transform;
}
void Viewport::_update_global_transform() {
	Transform2D sxform = stretch_transform * global_canvas_transform;
	RenderingServer::get_singleton()->viewport_set_global_canvas_transform(viewport, sxform);
}
void Viewport::set_global_canvas_transform(const Transform2D &p_transform) {
	ERR_MAIN_THREAD_GUARD;
	global_canvas_transform = p_transform;
	_update_global_transform();
}
Transform2D Viewport::get_global_canvas_transform() const {
	ERR_READ_THREAD_GUARD_V(Transform2D());
	return global_canvas_transform;
}
void Viewport::_camera_2d_set(Camera2D *p_camera_2d) {
	camera_2d = p_camera_2d;
}
void Viewport::_audio_listener_2d_set(AudioListener2D *p_listener) {
	if (audio_listener_2d == p_listener) {
		return;
	} else if (audio_listener_2d) {
		audio_listener_2d->clear_current();
	}
	audio_listener_2d = p_listener;
}
void Viewport::_audio_listener_2d_remove(AudioListener2D *p_listener) {