feat(.env.example): add o1-mini and o1-preview to .env.example

[evrentan]

Pull Request Template

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• Please ensure that you have thoroughly read and understood the Contributing Docs before submitting your Pull Request.

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Summary

Please provide a brief summary of your changes and the related issue. Include any motivation and context that is relevant to your changes. If there are any dependencies necessary for your changes, please list them here.

Change Type

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• New feature (non-breaking change which adds functionality)

Testing

Please describe your test process and include instructions so that we can reproduce your test. If there are any important variables for your testing configuration, list them here.

o1-mini and o1-preview models are tested.

Test Configuration:

Checklist

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• My code adheres to this project's style guidelines
• I have performed a self-review of my own code
• I have commented in any complex areas of my code
• My changes do not introduce new warnings
• Local unit tests pass with my changes