Subscribe to Config Entities to delete invalid one

[MichelFR]

I noticed that already created config entities are not deleted when the container is not running anymore. As a result, containers that are no longer available are still being shown in Homeassistant. To fix this issue, I propose subscribing to the MQTT topic where we created the config entities with auto discovery. By doing this, we can delete invalid config entities appropriately by sending an empty payload.

To implement this feature, we will need to update the codebase to include the necessary MQTT subscription logic. Once the code is updated, we can test the functionality to ensure that invalid config entities are being deleted as expected.

This issue is being raised to track the progress of implementing the subscribe to config entities to delete invalid ones feature. If anyone has any suggestions or ideas on how to approach this issue, feel free to contribute to the project.