feat: COT trace response handling in evaluator and model classes

[hhh2210]

• Added support for storing raw generations in HFLM and VLLM models.
• Updated the evaluator to log warnings when the length of raw generations does not match processed responses.
• Modified response collection to include raw responses when available.

This improves the evaluation process by allowing access to the original generated outputs alongside processed responses.

[CLAassistant]

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