Add pipeline tag, paper, code, and citation links

This PR improves the model card for `HorizonTEL/AIGIBench` by:
- Adding the `pipeline_tag: image-classification`, which accurately categorizes the model as an AI-generated image detector and enhances its discoverability on the Hub.
- Linking directly to the associated paper: [Is Artificial Intelligence Generated Image Detection a Solved Problem?](https://huggingface.co/papers/2505.12335).
- Providing a link to the official GitHub repository: [https://github.com/HorizonTEL/AIGIBench](https://github.com/HorizonTEL/AIGIBench).
- Including the BibTeX citation for proper academic attribution.

These updates ensure that the model card is more informative, discoverable, and aligned with Hugging Face Hub best practices.

README.md

@@ -1,8 +1,10 @@
 ---
-license: cc-by-nc-sa-4.0
 datasets:
 - HorizonTEL/AIGIBench
+license: cc-by-nc-sa-4.0
+pipeline_tag: image-classification
 ---
+
 <div align="center">
  <br>
 <h1>Is Artificial Intelligence Generated Image Detection a Solved Problem?</h1>
@@ -19,10 +21,22 @@ datasets:
 <sup>1</sup>Nanjing University of Information Science and Technology <sup>2</sup>University of Siena
 </div>
 
+This model is a pre-trained checkpoint for the AI-Generated Image (AIGI) detector described in the paper [Is Artificial Intelligence Generated Image Detection a Solved Problem?](https://huggingface.co/papers/2505.12335).
+This checkpoint is from the AIGIBench in Setting-II: trained on 144K images generated by both SD-v1.4 and ProGAN, covering the same four object categories.
 
-**This repository is the official pre-trained checkpoints of the AIGIBench in Setting-II**: Training on 144K images generated by both SD-v1.4 and ProGAN, covering the same four object categories.
+For more details and code, please refer to the official GitHub repository: [https://github.com/HorizonTEL/AIGIBench](https://github.com/HorizonTEL/AIGIBench).
 
 If this project helps you, please fork, watch, and give a star to this repository.  
 
 ## Contact
-If you have any question about this project, please feel free to contact 247918horizon@gmail.com
+If you have any question about this project, please feel free to contact 247918horizon@gmail.com
+
+## Citation
+```
+@inproceedings{li2025artificial,
+  title={Is Artificial Intelligence Generated Image Detection a Solved Problem?},
+  author={Li, Ziqiang and Yan, Jiazhen and He, Ziwen and Zeng, Kai and Jiang, Weiwei and Xiong, Lizhi and Fu, Zhangjie},
+  booktitle={Advances in Neural Information Processing Systems},
+  year={2025}
+}
+```