Function build_commit_graph_bytes 

pub fn build_commit_graph_bytes(
    sorted_oids: &[ObjectId],
    infos: &HashMap<ObjectId, CommitGraphCommitInfo>,
    odb: &Odb,
    changed_paths: bool,
    bloom_settings: &BloomFilterSettings,
    base_chain: Option<&CommitGraphChain>,
    base_graph_hashes: &[[u8; 20]],
    max_new_filters: Option<u32>,
) -> Result<(Vec<u8>, BloomWriteStats)>

Build raw commit-graph bytes (without touching the filesystem).