Add library_name: transformers to metadata
This PR improves the model card by adding the library_name: transformers metadata tag.
This change is based on evidence from the config.json ("architectures": ["VibeVoiceForConditionalGeneration"], "transformers_version": "4.51.3") and preprocessor_config.json ("processor_class": "VibeVoiceProcessor"), indicating compatibility with the transformers library. Adding this tag will enable the automated "how to use" widget on the model page, making it easier for users to interact with the model.
No other changes are made, as the existing paper, code, and project page links are accurate, and no transformers Python sample usage was explicitly found in the GitHub README.
Update: best to merge this one when https://github.com/huggingface/transformers/pull/40546 is merged
