docs: add Azure Files support as persistent storage option

[apoorva-u-r]

Added documentation for using Azure Files as a persistent storage option in Ray Train.

• Setup instructions
• Notes for Kubernetes usage
• Performance considerations

Fixes #54054

[gemini-code-assist]

Code Review

This pull request adds documentation for using Azure Files as a persistent storage option. The new section provides setup instructions and notes for Kubernetes and performance. My review identifies a critical issue where the documentation suggests using an incorrect environment variable (RAY_STORAGE_PATH) for configuration. I've provided suggestions to correct this to use the standard RunConfig(storage_path=...) method, ensuring consistency with other shared filesystem configurations in the documentation and reflecting the correct usage in Ray Train.

[gemini-code-assist]

The documentation suggests using export RAY_STORAGE_PATH=/mnt/azurefiles to configure the storage path for Azure Files. However, RAY_STORAGE_PATH does not appear to be a valid environment variable used by Ray Train for this purpose.

Using RunConfig(storage_path=...) is the correct and consistent way to configure a shared filesystem path, as shown in other parts of this document (e.g., for NFS/HDFS). Please update the configuration instructions to use RunConfig.

Suggested change

	3. Configure Ray to write to this location by setting:
	.. code-block:: bash
	export RAY_STORAGE_PATH=/mnt/azurefiles
	3. Configure your Ray Train or Tune script to use this path via ``RunConfig(storage_path)``:
	.. code-block:: python
	# In your Trainer/Tuner setup
	run_config=train.RunConfig(storage_path="/mnt/azurefiles")

[gemini-code-assist]

Similar to the main setup instructions, the note for Kubernetes deployments incorrectly references the RAY_STORAGE_PATH environment variable. The correct approach is to configure the mounted volume path using RunConfig(storage_path=...) in the training script.

Suggested change

	- For Kubernetes deployments, mount the Azure Files share as a volume on every pod and set ``RAY_STORAGE_PATH`` as an environment variable.
	- For Kubernetes deployments, mount the Azure Files share as a volume on every pod and configure ``RunConfig(storage_path=...)`` to point to the mount path.

[github-actions]

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[github-actions]

This pull request has been automatically closed because there has been no more activity in the 14 days
since being marked stale.

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