### 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.
bool _gui_control_has_focus(const Control *p_control);
	void _gui_control_grab_focus(Control *p_control);
	void _gui_grab_click_focus(Control *p_control);
	void _post_gui_grab_click_focus();
	void _gui_accept_event();
	bool _gui_drop(Control *p_at_control, Point2 p_at_pos, bool p_just_check);
	friend class AudioListener2D;
	void _audio_listener_2d_set(AudioListener2D *p_listener);
	void _audio_listener_2d_remove(AudioListener2D *p_listener);
	friend class Camera2D;
	void _camera_2d_set(Camera2D *p_camera_2d);
	friend class CanvasLayer;
	void _canvas_layer_add(CanvasLayer *p_canvas_layer);
	void _canvas_layer_remove(CanvasLayer *p_canvas_layer);
	void _drop_mouse_over();
	void _drop_mouse_focus();
	void _drop_physics_mouseover(bool p_paused_only = false);
	void _update_canvas_items(Node *p_node);
	friend class Window;
	void _sub_window_update_order();
	void _sub_window_register(Window *p_window);
	void _sub_window_update(Window *p_window);
	void _sub_window_grab_focus(Window *p_window);
	void _sub_window_remove(Window *p_window);
	int _sub_window_find(Window *p_window) const;
	bool _sub_windows_forward_input(const Ref<InputEvent> &p_event);
	SubWindowResize _sub_window_get_resize_margin(Window *p_subwindow, const Point2 &p_point);
	void _update_mouse_over();
	void _update_mouse_over(Vector2 p_pos);
	virtual bool _can_consume_input_events() const { return true; }