### 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_FAIL_COND(window_id == DisplayServer::INVALID_WINDOW_ID);
	mode = (Mode)DisplayServer::get_singleton()->window_get_mode(window_id);
	for (int i = 0; i < FLAG_MAX; i++) {
		flags[i] = DisplayServer::get_singleton()->window_get_flag(DisplayServer::WindowFlags(i), window_id);
	}
}
void Window::_clear_window() {
	ERR_FAIL_COND(window_id == DisplayServer::INVALID_WINDOW_ID);
	bool had_focus = has_focus();
	if (transient_parent && transient_parent->window_id != DisplayServer::INVALID_WINDOW_ID) {
		DisplayServer::get_singleton()->window_set_transient(window_id, DisplayServer::INVALID_WINDOW_ID);
	}
	for (const Window *E : transient_children) {
		if (E->window_id != DisplayServer::INVALID_WINDOW_ID) {
			DisplayServer::get_singleton()->window_set_transient(E->window_id, DisplayServer::INVALID_WINDOW_ID);
		}
	}
	_update_from_window();
	DisplayServer::get_singleton()->delete_sub_window(window_id);
	window_id = DisplayServer::INVALID_WINDOW_ID;
	
	if (had_focus && transient_parent) {
		transient_parent->grab_focus();
	}
	_update_viewport_size();
	RS::get_singleton()->viewport_set_update_mode(get_viewport_rid(), RS::VIEWPORT_UPDATE_DISABLED);
}
void Window::_rect_changed_callback(const Rect2i &p_callback) {