This PR populates the dataset card for the ELF datasets. It includes:
- Metadata for task categories (`text-generation`) and license (`mit`).
- Links to the paper [ELF: Embedded Language Flows](https://huggingface.co/papers/2605.10938) and the official GitHub repository.
- A sample usage section demonstrating how to load the pre-tokenized datasets using the `datasets` library.
- The BibTeX citation for the paper.