### 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.
for (Camera3D *E : camera_3d_set) {
					if (first == nullptr || first->is_greater_than(E)) {
						first = E;
					}
				}
				if (first) {
					first->make_current();
				}
			}
#endif 
		} break;
		case NOTIFICATION_EXIT_TREE: {
			_gui_cancel_tooltip();
			RenderingServer::get_singleton()->viewport_set_scenario(viewport, RID());
			RenderingServer::get_singleton()->viewport_remove_canvas(viewport, current_canvas);
			if (contact_2d_debug.is_valid()) {
				RenderingServer::get_singleton()->free(contact_2d_debug);
				contact_2d_debug = RID();
			}
			if (contact_3d_debug_multimesh.is_valid()) {
				RenderingServer::get_singleton()->free(contact_3d_debug_multimesh);
				RenderingServer::get_singleton()->free(contact_3d_debug_instance);
				contact_3d_debug_instance = RID();
				contact_3d_debug_multimesh = RID();
			}
			remove_from_group("_viewports");
			set_physics_process_internal(false);
			RS::get_singleton()->viewport_set_active(viewport, false);
			RenderingServer::get_singleton()->viewport_set_parent_viewport(viewport, RID());
		} break;