Update size category and add paper link to PerCoR dataset card

This PR updates the `size_categories` metadata from `10K<n<100K` to `100K<n<1M` to accurately reflect the dataset's size of ~106K instances, as stated in the paper abstract and the dataset card content.

It also adds a direct link to the paper, [PerCoR: Evaluating Commonsense Reasoning in Persian via Multiple-Choice Sentence Completion](https://huggingface.co/papers/2510.22616), in the dataset card content for easier access and improved discoverability.

README.md

@@ -1,15 +1,18 @@
 ---
+language:
+- fa
 license: apache-2.0
+size_categories:
+- 100K<n<1M
 task_categories:
 - question-answering
 - text-classification
-language:
-- fa
-size_categories:
-- 10K<n<100K
 ---
+
 # 📘 PerCoR: Persian Commonsense Reasoning (Multiple-Choice Sentence Completion)
 
+Paper: [PerCoR: Evaluating Commonsense Reasoning in Persian via Multiple-Choice Sentence Completion](https://huggingface.co/papers/2510.22616)
+
 **PerCoR** is a large-scale Persian benchmark for **commonsense reasoning** in a **4-choice sentence-completion** format.  
 It contains **~106K** examples from **40+** Persian websites across news, culture, lifestyle, tech, religion, travel, and more.  
 Each instance provides a **prefix** (context) and **four candidate completions** — one correct and three distractors.