[WIP] Support/togetherai

[JackHopkins]

Description of change

Support for TogetherAI, and a test.

Pull-Request Checklist

• Code is up-to-date with the main branch
• npm run lint passes with this change
• npm run test passes with this change
• This pull request links relevant issues as Fixes #0000
• There are new or updated unit tests validating the change
• Documentation has been updated to reflect this change
• The new commits follow conventions outlined in the conventional commit spec

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