Model handlers support and config updates

[Dornavineeth]

What does this PR do?

• Adds support for model handlers beyond AutoModelForCausalLM
• Support Probe models
• Added support for evaluation on paraphrased questions on tofu
• Define batch_size as global variable in eval.tofu.batch_size

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• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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