When a client re-registers with the model registry, its previous status for a given model (e.g., quota exceeded or suspended) was not being cleared. This could lead to a situation where a client is permanently unable to use a model even after re-registering. This change ensures that when a client re-registers an existing model, its ID is removed from the model's `QuotaExceededClients` and `SuspendedClients` lists. This effectively resets the client's status for that model, allowing for a fresh start upon reconnection.