### 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;
	ERR_FAIL_COND(!is_inside_tree());
	ERR_FAIL_COND_MSG(window_id == DisplayServer::MAIN_WINDOW_ID, "Can't popup the main window.");
	ERR_FAIL_COND_MSG(p_ratio <= 0.0 || p_ratio > 1.0, "Ratio must be between 0.0 and 1.0!");
	Rect2 parent_rect;
	if (is_embedded()) {
		parent_rect = get_embedder()->get_visible_rect();
	} else {
		DisplayServer::WindowID parent_id = get_parent_visible_window()->get_window_id();
		int parent_screen = DisplayServer::get_singleton()->window_get_current_screen(parent_id);
		parent_rect.position = DisplayServer::get_singleton()->screen_get_position(parent_screen);
		parent_rect.size = DisplayServer::get_singleton()->screen_get_size(parent_screen);
	}
	Rect2i popup_rect;
	if (parent_rect != Rect2()) {
		popup_rect.size = parent_rect.size * p_ratio;
		popup_rect.size = _clamp_window_size(popup_rect.size);
		popup_rect.position = parent_rect.position + (parent_rect.size - popup_rect.size) / 2;
	}
	popup(popup_rect);
}
void Window::popup(const Rect2i &p_screen_rect) {