Nathan unify modelargs

[NathanHB]

• removed override batch size and made it part of model config
• remove env config, config should be part of env directly, no need to load it up
• better loading of models
  • baseclass for model configs, allows parsing of model config through cli or config file.
  • Unified naming for model args, i.e. model_name
• removed openai endpoint, we can just use litellm for this, same for TGI and inference endpoints we don't really need it and it's better to have one interface

[NathanHB]

this should not be needed as it is an issue with tokenizer version or config

[HuggingFaceDocBuilderDev]

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