### 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.
physics_server_2d = PhysicsServer2DManager::get_singleton()->new_default_server();
			physics_server_2d->init();
			navigation_server_3d = NavigationServer3DManager::new_default_server();
			navigation_server_2d = memnew(NavigationServer2D);
			memnew(InputMap);
			InputMap::get_singleton()->load_default();
			theme_db = memnew(ThemeDB);
			theme_db->initialize_theme_noproject();
			memnew(SceneTree);
			SceneTree::get_singleton()->initialize();
			if (!DisplayServer::get_singleton()->has_feature(DisplayServer::Feature::FEATURE_SUBWINDOWS)) {
				SceneTree::get_singleton()->get_root()->set_embedding_subwindows(true);
			}
			return;
		}
		if (name.find("Audio") != -1) {
			
			int dummy_idx = AudioDriverManager::get_driver_count() - 1;
			AudioDriverManager::initialize(dummy_idx);
			AudioServer *audio_server = memnew(AudioServer);
			audio_server->init();
			return;
		}
		if (suite_name.find("[Navigation]") != -1 && navigation_server_2d == nullptr && navigation_server_3d == nullptr) {
			navigation_server_3d = NavigationServer3DManager::new_default_server();
			navigation_server_2d = memnew(NavigationServer2D);
			return;
		}
	}
	void test_case_end(const doctest::CurrentTestCaseStats &) override {