Verifies that the model specified in this ModelUsage is available on the connection.
Creates a temporary client, fetches the list of available models from the server, and checks if the model name exists in the available models. Updates the `is_valid` property based on the verification result.
Returns false if connection is empty, model is empty, connection is not found, or if there's an error fetching models. Returns true only if the model is available.
| config |
The Config2 instance containing the connection configuration |
|
true if the model is available, false otherwise |