Add new GPT 5 and GPT OSS models

[Ayfri]

Hello, could you add the two new family of models as of August 2025!

[niieani]

Would love to, but OpenAI needs to expose the new tokenizers upstream. Track the issue on their repo.

[github-actions]

🎉 This issue has been resolved in version 3.1.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀