Add paper link, code link, and license metadata

Hi! I'm Niels from the Hugging Face community science team.

I'm opening this PR to improve the dataset card for Copiale Lines. This includes:
- Adding the **MIT license** to the metadata.
- Adding a link to the associated **paper** on the Hugging Face Hub.
- Adding a link to the **official GitHub repository**.

These changes help researchers find, cite, and use your work more effectively.

README.md

@@ -1,11 +1,12 @@
 ---
-pretty_name: Copiale Lines
-task_categories:
-- image-to-text
 language:
 - de
+license: mit
 size_categories:
 - 1K<n<10K
+task_categories:
+- image-to-text
+pretty_name: Copiale Lines
 viewer: true
 ---
 
@@ -13,7 +14,9 @@ viewer: true
 
 Copiale Lines is a line-level image-to-text dataset for historical cipher decipherment. It contains cropped line images from the Copiale manuscript paired with plaintext ground truth.
 
-This dataset is used in the paper *Learning to Decipher from Pixels: A Case Study of Copiale* (HistoCrypt 2026).
+This dataset was presented in the paper [Learning to Decipher from Pixels -- A Case Study of Copiale](https://huggingface.co/papers/2604.23683) (HistoCrypt 2026).
+
+**Code:** [https://github.com/leitro/Decipher-from-Pixels-Copiale](https://github.com/leitro/Decipher-from-Pixels-Copiale)
 
 ## Dataset Structure