When `inject_lora()` replaces Linear layers with LoRALinear after the model
has been moved to CUDA, the new lora_A and lora_B parameters were always
created on CPU, causing a device mismatch error during the forward pass.
Now lora_A and lora_B are created on the same device and dtype as the
parent weight, matching the model's current device.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>