### 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.
#include "viewport.h"
#include "core/config/project_settings.h"
#include "core/debugger/engine_debugger.h"
#include "core/object/message_queue.h"
#include "core/string/translation.h"
#include "core/templates/pair.h"
#include "core/templates/sort_array.h"
#include "scene/2d/audio_listener_2d.h"
#include "scene/2d/camera_2d.h"
#include "scene/2d/collision_object_2d.h"
#ifndef _3D_DISABLED
#include "scene/3d/audio_listener_3d.h"
#include "scene/3d/camera_3d.h"
#include "scene/3d/collision_object_3d.h"
#include "scene/3d/world_environment.h"
#endif 
#include "scene/gui/control.h"
#include "scene/gui/label.h"
#include "scene/gui/popup.h"
#include "scene/gui/popup_menu.h"
#include "scene/gui/subviewport_container.h"
#include "scene/main/canvas_layer.h"
#include "scene/main/window.h"