Fix ChildFailedError

✅ Solution

The "ChildFailedError" in PEFT often arises from inconsistencies between the LoRA adapter's configuration and the base model's structure or data types during operations like merging or loading. To resolve this, ensure the LoRA configuration (`peft_config.json`) matches the base model's architecture and that the datatypes used for the LoRA layers are compatible with the base model's weights; specifically setting `torch_dtype` in `LoraConfig` and when loading the base model can help. If using FSDP, carefully manage device placement and sharding to avoid inconsistencies during merging.