transformers gguf human feedback rlhf preferences alignment HALO halos dpo rl en dataset:stanfordnlp/SHP dataset:Anthropic/hh-rlhf dataset:OpenAssistant/oasst1 base_model:ContextualAI/archangel_sft-kto_llama30b base_model:quantized:ContextualAI/archangel_sft-kto_llama30b license:apache-2.0 endpoints_compatible region:us imatrix