fix: remove lora_config.json to fix auto-detection routing

Merged LoRA models should use Traditional BERT path, not LoRA path. The presence of lora_config.json causes auto-detection to route to LoRA classifier which fails. This file is not needed for merged models.

lora_config.json

@@ -1 +0,0 @@
-{"rank": 16, "alpha": 32, "dropout": 0.1, "target_modules": ["attn.Wqkv", "attn.Wo", "mlp.Wi", "mlp.Wo"]}