Changes to list llms

added the non-success response with the status 503

removed the advanced_voice enum value from the data/items/llmFormat response property for the response status 200

added the optional property data/items/isDeprecated to the response with the 200 status

the response property data/items/reasoningEffort became nullable for the status 200

the response property data/items/reasoningFormat became nullable for the status 200

added the new undefined enum value to the data/items/reasoningFormat response property for the response status 200

added the non-success response with the status 403

removed the default enum value from the data/items/reasoningEffort response property for the response status 200

removed the high enum value from the data/items/reasoningEffort response property for the response status 200

removed the low enum value from the data/items/reasoningEffort response property for the response status 200

removed the medium enum value from the data/items/reasoningEffort response property for the response status 200

removed the raw enum value from the data/items/reasoningFormat response property for the response status 200