fix ollama issue

[morioka]

• fix OllamaLanguageModel constructor argument name.
• add "how to use with ollama" to README.md

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[aksg87]

Thank you @morioka for identifying the model vs model_id parameter mismatch.

PR #57 has been created focusing solely on the parameter fix to streamline the review process, as it separates the core fix from documentation changes. Additional Ollama documentation is being prepared separately.

Your contribution in discovering this issue is valued. Please continue to share any feedback or issues you encounter with Ollama integration.