[DOC] Documentation changes for Snapshot Status API for 2.17 and above

[ltaragi]

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Tell us about your request. Provide a summary of the request.
This documentation change addresses the necessary changes to Snapshot Status API as part of V2 snapshots:

• Allow index filter in the status API if the request contains only one snapshot name. Thus, the status API response will only consist of the specified indices in the filter (if any).
• For non-shallow-V2 snapshots:
  • The status API call works only if the total number of shards across the requested resources (snapshots or the indices of a particular snapshot) is less than a certain amount determined by the cluster setting snapshot.max_shards_allowed_in_status_api
• For shallow snapshots of type V2, the file count and size stats are 0 at all levels. For these snapshots, snapshot.max_shards_allowed_in_status_api cluster setting is not honoured

*Version: List the OpenSearch version to which this issue applies, e.g. 2.14, 2.12--2.14, or all.
2.17 and above

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.
PR for the mentioned changes - opensearch-project/OpenSearch#15463