Support SkyReels-A1 for expressive portrait animation.

### Model/Pipeline/Scheduler description

[https://github.com/SkyworkAI/SkyReels-A1](https://github.com/huggingface/diffusers/issues/url) is a creative productivity tool that can transfer expressions and motions onto the portrait. Can diffusers support it, so that the community can simply use this project, thanks.

**Open source status:**
- [x] The model implementation is available.
- [x] The model weights are available.

**Provide useful links for the implementation**
Official implementation: https://github.com/SkyworkAI/SkyReels-A1
Model weights: https://huggingface.co/Skywork/SkyReels-A1

### Open source status

- [x] The model implementation is available.
- [x] The model weights are available (Only relevant if addition is not a scheduler).

### Provide useful links for the implementation

_No response_

Start by reviewing the official SkyReels-A1 implementation and the model weights linked in the issue, then determine how the model should be integrated into Diffusers. Done means Diffusers supports SkyReels-A1 for expressive portrait animation using the available implementation and weights.

Scritto dal modello di indicizzazione a partire dal testo della issue.