nil-hover-reject-mbert

Fine-tuned mBERT for hover reject-unsuitable (EN↔ZH).

• Not the pick-best model (aarontseng/nil-hover-mbert).
• Training data: aarontseng/nil-hover-reject-cmn-hani
• Checkpoint: checkpoint-16000 (best item_accuracy / set_acc = 0.2746)
• Early-stop metric: exact reject-set match (item_accuracy)
• Inference: reject when contradiction > entailment (logits); keep the rest.