Add RayJob and Slurm support for Ray APIs + integration with run.Experiment

[hemildesai]

Usage with RayCluster API:

cluster = RayCluster(
        name="test",
        executor=your_slurm_executor,
        # pre_ray_start_commands=[
        #     "pip install uv && echo 'unset RAY_RUNTIME_ENV_HOOK' >> /home/ray/.bashrc"
        # ],
)
job_id = cluster.schedule_job(
        name="test_job",
        executor=executor,
        command=command,
        workdir="path-to-your-workdir",
)
cluster.start(...)
cluster.stop(...)
cluster.port_forward(...)

Usage with run.Experiment

task = run.Script(inline=command, metadata={"use_with_ray_cluster": True})

with run.Experiment("test_ray_experiment") as exp:
    exp.add(task, executor=your_slurm_executor, name="test_ray_task")
    exp.run(detach=False, tail_logs=True)

To fix the issue, we will add an explicit return None at the end of the start function. This ensures that the function's return behavior is clear and consistent, even if it is not intended to return a meaningful value. The change will be made at the end of the start function, after all existing logic.

---

[gwarmstrong]

Works for me now!