Function write_segment_with_graph 

pub fn write_segment_with_graph(
    vfs: &dyn Vfs,
    directory: &Path,
    build: SegmentBuild<'_>,
    graph: GraphNodeBlockBuild<'_>,
    policy: DurabilityPolicy,
) -> Result<SegmentMeta, SegmentError>

Writes and atomically publishes a segment containing fixed-stride graph blocks.