Add library_name to metadata

This PR adds the `library_name` tag to the model card metadata. The model uses the `diffusers` library, so this tag will help users easily identify the appropriate framework for using this model.

README.md

@@ -9,6 +9,7 @@ license: other
 license_name: flux.1-dev-non-commercial-license
 license_link: LICENSE
 pipeline_tag: image-to-image
+library_name: diffusers
 ---
 
 [![Paper](https://img.shields.io/badge/%20arXiv-Paper-red)](https://arxiv.org/abs/2506.03107)