bug: preserve Redfish OEM extensions in health log records

[jayzhudev]

Version

main

Describe the bug.

Redfish events and log entries can include vendor-specific diagnostic data under Oem:

nv-redfish preserves this data during deserialization, but hardware-health drops it when converting Redfish records into LogRecord.

Both collection modes are affected:

• SSE mode maps Redfish EventRecord values.
• Periodic mode maps Redfish LogEntry values.

Downstream log consumers therefore cannot access vendor error identifiers or other OEM diagnostics.

Minimum reproducible example

Relevant log output

Other/Misc.

No response

Code of Conduct

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• I have searched the open bugs and have found no duplicates for this bug report