Add number as a valid type for `CartesiaOptions.speed`

[clostao]

Describe the problem

When using inference.TTS with a model from Cartesia within modelOptions is available a parameter speed.

The model options are defined by this interface:

export interface CartesiaOptions {
  /** Maximum duration of audio in seconds. */
  duration?: number;
  /** Speech speed. Default: not specified. */
  speed?: 'slow' | 'normal' | 'fast';
}

Cartesia does not only admit these values but numeric values too, where 1.0 represent 'normal'. I'd want to add support in CartesiaOptions interface for using numbers too. For some use cases 'fast' is too fast and 'normal' too slow.

Describe the proposed solution

Update CartesiaOptions interface to:

export interface CartesiaOptions {
  /** Maximum duration of audio in seconds. */
  duration?: number;
  /** Speech speed. Default: not specified. */
  speed?: 'slow' | 'normal' | 'fast' | number;
}

I think that there are no more changes needed since I'm using this config and is working alright:

tts: new inference.TTS({
       model: 'cartesia/sonic-3',
       voice: 'd4db5fb9-f44b-4bd1-85fa-192e0f0d75f9',
       language: 'es',
       modelOptions: {
       // eslint-disable-next-line @typescript-eslint/no-explicit-any
       speed: 1.25 as any,
       },
 }),

Alternatives considered

No response

Importance

nice to have

Additional Information

No response