Uploads a buffer to FileStorageEngine and returns the created MJ: Files ID.
Returns undefined when no storage accounts are configured or when Config / UploadFile
throws. Never throws so callers can fall back to inline payloads or emit non-fatal warnings.
Uploads a buffer to
FileStorageEngineand returns the createdMJ: FilesID.Returns
undefinedwhen no storage accounts are configured or whenConfig/UploadFilethrows. Never throws so callers can fall back to inline payloads or emit non-fatal warnings.