### 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);
	uint32_t f = 0;
	for (int i = 0; i < FLAG_MAX; i++) {
		if (flags[i]) {
			f |= (1 << i);
		}
	}
	DisplayServer::VSyncMode vsync_mode = DisplayServer::get_singleton()->window_get_vsync_mode(DisplayServer::MAIN_WINDOW_ID);
	Rect2i window_rect;
	if (initial_position == WINDOW_INITIAL_POSITION_ABSOLUTE) {
		window_rect = Rect2i(position, size);
	} else if (initial_position == WINDOW_INITIAL_POSITION_CENTER_PRIMARY_SCREEN) {
		window_rect = Rect2i(DisplayServer::get_singleton()->screen_get_position(DisplayServer::SCREEN_PRIMARY) + (DisplayServer::get_singleton()->screen_get_size(DisplayServer::SCREEN_PRIMARY) - size) / 2, size);
	} else if (initial_position == WINDOW_INITIAL_POSITION_CENTER_MAIN_WINDOW_SCREEN) {
		window_rect = Rect2i(DisplayServer::get_singleton()->screen_get_position(DisplayServer::SCREEN_OF_MAIN_WINDOW) + (DisplayServer::get_singleton()->screen_get_size(DisplayServer::SCREEN_OF_MAIN_WINDOW) - size) / 2, size);
	} else if (initial_position == WINDOW_INITIAL_POSITION_CENTER_OTHER_SCREEN) {
		window_rect = Rect2i(DisplayServer::get_singleton()->screen_get_position(current_screen) + (DisplayServer::get_singleton()->screen_get_size(current_screen) - size) / 2, size);
	} else if (initial_position == WINDOW_INITIAL_POSITION_CENTER_SCREEN_WITH_MOUSE_FOCUS) {
		window_rect = Rect2i(DisplayServer::get_singleton()->screen_get_position(DisplayServer::SCREEN_WITH_MOUSE_FOCUS) + (DisplayServer::get_singleton()->screen_get_size(DisplayServer::SCREEN_WITH_MOUSE_FOCUS) - size) / 2, size);
	} else if (initial_position == WINDOW_INITIAL_POSITION_CENTER_SCREEN_WITH_KEYBOARD_FOCUS) {
		window_rect = Rect2i(DisplayServer::get_singleton()->screen_get_position(DisplayServer::SCREEN_WITH_KEYBOARD_FOCUS) + (DisplayServer::get_singleton()->screen_get_size(DisplayServer::SCREEN_WITH_KEYBOARD_FOCUS) - size) / 2, size);
	}
	window_id = DisplayServer::get_singleton()->create_sub_window(DisplayServer::WindowMode(mode), vsync_mode, f, window_rect);
	ERR_FAIL_COND(window_id == DisplayServer::INVALID_WINDOW_ID);
	DisplayServer::get_singleton()->window_set_max_size(Size2i(), window_id);
	DisplayServer::get_singleton()->window_set_min_size(Size2i(), window_id);
	DisplayServer::get_singleton()->window_set_mouse_passthrough(mpath, window_id);
	String tr_title = atr(title);
#ifdef DEBUG_ENABLED