🚀[FEA]: Adding GenCast

[mariusaurus]

Is this a new feature, an improvement, or a change to existing functionality?

New Feature

How would you describe the priority of this feature request

Critical (currently preventing usage)

Please provide a clear description of problem you would like to solve.

Could we have GenCast added to the list of supported global AI weather models?
GenCast is one of few non-deterministic AI weather models and enable users to build ensemble workflows.

[ViokingTung]

hi,in order to integrate gencast into earth2studio, can we simply follow these steps:

1. Depends on the official graphcast package. GenCast is actually part of the graphcast package.
2. Adapt the official Graphcast package (which provides the core model architecture, inference logic, and checkpoint loading) to Earth2Studio using the Wrapper Pattern. The specific adaptation is as follows:
   • Interface specifications (PrognosticModel, AutoModelMixin, etc.)
   • coordinate system
   • Tensor format conversion: PyTorch Tensor ↔ JAX Array ↔ xarray Dataset
   • Interface standardization: Implement standard methods such as input_coords(), output_coords(), call(), and create_iterator().
   • Model loading: Loading weights from Google Cloud Storage via the Package class

is it right?