Does this project require CUDA 12.8?

I notice in the [pyproject.toml](pyproject.toml), the CUDA version is pinned to 12.8. Is this necessary for running the package?

When I manually edit the file to point to the PyTorch CUDA 12.4 versions, I am unable to install the package.

**Repro**:
1. Create uv venv
2. Update all references to 128 with 124 in pyproject.toml
3. ``uv sync``

```bash
× No solution found when resolving dependencies:
╰─▶ Because there is no version of torch==2.7.0 and nemo-rl depends on torch==2.7.0, we can conclude that nemo-rl's requirements are unsatisfiable.
And because your workspace requires nemo-rl[mcore], we can conclude that your workspace's requirements are unsatisfiable.
```

Start with pyproject.toml and reproduce the reported failure using a uv venv and uv sync after changing CUDA references from 128 to 124. Trace the torch==2.7.0 dependency resolution and compare the relevant package requirements. Done means documenting whether CUDA 12.8 is required and making the supported configuration install successfully, if a change is appropriate.

Written by the indexing model from the issue text.