Add pipeline tag, paper and code links

This PR improves the model card by:
- Adding the `pipeline_tag: image-classification` to ensure discoverability for users looking for AI-generated image detectors.
- Including direct links to the paper ([Is Artificial Intelligence Generated Image Detection a Solved Problem?](https://huggingface.co/papers/2505.12335)) and the GitHub repository (https://github.com/HorizonTEL/AIGIBench) within the model card content.

Please review and merge if these changes are appropriate.

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>
@@ -22,6 +24,9 @@ datasets:
 
 **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.
 
+**Paper:** [Is Artificial Intelligence Generated Image Detection a Solved Problem?](https://huggingface.co/papers/2505.12335)
+**Code/Project Page:** https://github.com/HorizonTEL/AIGIBench
+
 If this project helps you, please fork, watch, and give a star to this repository.  
 
 ## Contact