sentence-transformers safetensors xlm-roberta sentence-similarity feature-extraction dataset_size:100K<n<1M loss:MultipleNegativesRankingLoss arxiv:1908.10084 arxiv:1705.00652 base_model:FacebookAI/xlm-roberta-base base_model:finetune:FacebookAI/xlm-roberta-base autotrain_compatible text-embeddings-inference endpoints_compatible region:us