- Update product description to reference Claude 4 Sonnet instead of Claude 3.5 Sonnet
- Change default model from `claude-3-7-sonnet-latest` to `claude-sonnet-4-0`
- Add new model options: `claude-sonnet-4-0` and `claude-opus-4-0`
- Remove outdated model options: `claude-3-sonnet-20240229` and `claude-3-haiku-20240307`
- Update keywords to use "Claude Sonnet" instead of "Claude 3.5"
- Slightly revise token usage description for clarity

- Update test to reflect new default model choice.

- Update all references to Claude models in the README.md file, changing from Claude 3.5 Sonnet to Claude 4 Sonnet in the features section
- Update the model options table to reflect the latest available Claude models.
- Set "claude-sonnet-4-0" as the new default model.

## [0.3.9](diff-commit-v0.3.8...diff-commit-v0.3.9) (2025-06-04)


### Documentation

* **models:** update Claude model references to Claude 4 ([f74c4c6](f74c4c6))


### DX Maintenance & Configuration

* **config:** update default model to claude-sonnet-4-0 ([f555e81](f555e81))
* **models:** update Claude model references to Claude 4 Sonnet ([81315f8](81315f8))


### DX Testing

* **anthropic:** update Claude model name to "claude-sonnet-4-0" ([887980c](887980c))

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