sentence-transformers safetensors bert sentence-similarity feature-extraction dataset_size:1M<n<10M loss:TripletLoss arxiv:1908.10084 arxiv:1703.07737 base_model:sentence-transformers/paraphrase-MiniLM-L12-v2 base_model:finetune:sentence-transformers/paraphrase-MiniLM-L12-v2 model-index autotrain_compatible text-embeddings-inference endpoints_compatible region:us