This PR enhances the DENTEX dataset card by:
- Adding `task_categories` (`object-detection`, `image-classification`) and `tags` (`medical`, `x-ray`, `dental`) to the metadata. This significantly improves the dataset's discoverability on the Hugging Face Hub.
- Including prominent, top-level links to the associated [Paper](https://huggingface.co/papers/2305.19112), [Code](https://github.com/ibrahimethemhamamci/DENTEX), and [Project Page](https://dentex.grand-challenge.org) for immediate access to key resources.
- Removing the redundant `
