This PR improves the dataset card for `umd-zhou-lab/ChartAlignBench` by:
- Adding `task_categories: ['image-text-to-text']` to the metadata, allowing the dataset to be more easily discovered on the Hugging Face Hub.
- Adding `language: ['en']` to the metadata, as the dataset content and documentation are in English.
- Updating the placeholder links to the paper ([`huggingface.co/papers/2510.26781`](https://huggingface.co/papers/2510.26781)) and GitHub repository ([`github.com/tianyi-lab/ChartAlignBench`](https://github.com/tianyi-lab/ChartAlignBench)) in the content section.
- Adding `python` to the code block for syntax highlighting in the sample usage.
