Improve model card: Update pipeline tag, add library name, and paper link

This PR improves the model card for CHURRO by:
- Updating the `pipeline_tag` from `image-text-to-text` to `image-to-text` for better discoverability and accuracy for a historical text recognition model.
- Adding `library_name: transformers` to correctly identify the model's compatibility with the Hugging Face Transformers library, enabling the automated code snippet on the Hub.
- Updating the placeholder arXiv paper link in the model card content to the correct one: `https://arxiv.org/abs/2509.19768`.

README.md

@@ -1,14 +1,15 @@
 ---
+base_model:
+- Qwen/Qwen2.5-VL-3B-Instruct
+datasets:
+- stanford-oval/churro
 license: other
 license_name: qwen-research
 license_link: LICENSE
-datasets:
-- stanford-oval/churro
-base_model:
-- Qwen/Qwen2.5-VL-3B-Instruct
-pipeline_tag: image-text-to-text
+pipeline_tag: image-to-text
 tags:
 - historical
+library_name: transformers
 ---
 
 <p align="center">
@@ -17,7 +18,7 @@ tags:
 	<p align="center">
 		<a href="https://huggingface.co/stanford-oval/churro-3B" target="_blank"><img src="https://img.shields.io/badge/Model-CHURRO%203B-8A4FFF" alt="Model" /></a>
         <a href="https://huggingface.co/datasets/stanford-oval/churro-dataset" target="_blank"><img src="https://img.shields.io/badge/Dataset-CHURRO--DS-0A7BBB" alt="Dataset" /></a>
-		<a href="https://arxiv.org/abs/0000.00000" target="_blank"><img src="https://img.shields.io/badge/Paper-arXiv%20(preprint%20pending)-B31B1B" alt="Paper" /></a>
+		<a href="https://arxiv.org/abs/2509.19768" target="_blank"><img src="https://img.shields.io/badge/Paper-arXiv-B31B1B" alt="Paper" /></a>
 		<a href="https://github.com/stanford-oval/churro/stargazers" target="_blank"><img src="https://img.shields.io/github/stars/stanford-oval/churro?style=social" alt="GitHub Stars" /></a>
 	</p>
 </p>