Bug fix: 6012573 (#1131)

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<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Chores**
  * Standardized the configuration key for model precision.
* Model loading now defaults to bfloat16 precision instead of float32,
aligning configs and runtime behavior.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Signed-off-by: Suguna Velury <178320438+sugunav14@users.noreply.github.com>

Author: sugunav14

examples/gpt-oss/configs/sft_full.yaml

@@ -1,7 +1,7 @@
 # Model
 model_name_or_path: openai/gpt-oss-20b
 attn_implementation: eager
-torch_dtype: bfloat16
+dtype: bfloat16
 
 # Dataset
 dataset_name: HuggingFaceH4/Multilingual-Thinking

examples/gpt-oss/configs/sft_lora.yaml

@@ -1,7 +1,7 @@
 # Model
 model_name_or_path: openai/gpt-oss-20b
 attn_implementation: eager
-torch_dtype: bfloat16
+dtype: bfloat16
 
 # Dataset
 dataset_name: HuggingFaceH4/Multilingual-Thinking

examples/gpt-oss/sft.py

@@ -72,7 +72,7 @@ def main(script_args, training_args, model_args, quant_args):
         "revision": model_args.model_revision,
         "trust_remote_code": model_args.trust_remote_code,
         "attn_implementation": model_args.attn_implementation,
-        "torch_dtype": getattr(model_args, "dtype", "float32"),
+        "torch_dtype": getattr(model_args, "dtype", "bfloat16"),
         "use_cache": not training_args.gradient_checkpointing,
     }