Improve model card: Add metadata (tags, library name, pipeline tag) and GitHub link

This PR enhances the model card for the LexGenius model by:

* Adding relevant metadata:
* `license: cc-by-nc-4.0` (following majority vote from peer review).
* `library_name: transformers` as the model's `config.json` indicates compatibility with the Hugging Face Transformers library. This enables the "how to use" widget.
* `pipeline_tag: question-answering` to accurately reflect the model's purpose in evaluating legal intelligence through questions.
* `tags: [chinese, legal]` for improved discoverability on the Hugging Face Hub, reflecting the model's domain and language.
* Adding a GitHub repository badge to the top section for easier access to the project's code.

These additions will improve the model's discoverability and utility on the Hugging Face Hub.

README.md

@@ -1,3 +1,12 @@
+---
+license: cc-by-nc-4.0
+library_name: transformers
+pipeline_tag: question-answering
+tags:
+- chinese
+- legal
+---
+
 # LexGenius: An Expert-Level Benchmark for Large Language Models in Chinese Legal General Intelligence
 
 <div align="center">
@@ -6,6 +15,7 @@
 [![Homepage](https://img.shields.io/badge/Homepage-LexGenius-0A66C2.svg)](https://qwenqking.github.io/LexGenius/)
 [![Dataset](https://img.shields.io/badge/Dataset-HuggingFace-orange.svg)](https://huggingface.co/datasets/QwenQKing/LexGenius)
 [![HF Models](https://img.shields.io/badge/HF%20Models-HuggingFace-yellow.svg)](https://huggingface.co/QwenQKing/LexGenius)
+[![GitHub Code](https://img.shields.io/badge/GitHub-Code-blue.svg)](https://github.com/QwenQKing/LexGenius)
 [![Email Contact](https://img.shields.io/badge/Contact-wenjinliu23%40outlook.com-red.svg?logo=microsoftoutlook&logoColor=white&style=flat)](mailto:wenjinliu23@outlook.com)