Stg104/nfs listv2

[browndav-msft]

#Summary
Adds support for XNFS ListFilesV2 REST API enhancements to return extended metadata for NFS files directly from the list response.
#Changes

• Enables extended properties for NFS files in ListFiles (timestamps, ETag, UID/GID, mode, link count, NFS attributes, etc.)
• Ensures up-to-date Content-Length and timestamps by reconciling namespace and blob data
• Introduces consistency tracking (stateful/stateless flags) to determine when data must be fetched from blob storage
• Adds support for special file types (symlink, device files, FIFO, socket) in responses
• Implements batched blob fetches for files with stale metadata
• Introduces backfill mechanism to update existing namespace rows and reduce future lookup cost

#Impact

• Eliminates need for per-file GET calls to retrieve metadata
• Improves performance and scalability for scenarios like backup validation
• Aligns NFS behavior with SMB ListFilesV2 capabilities