Function identity_raw_for_serialized_commit 

pub fn identity_raw_for_serialized_commit(
    encoding: &Option<String>,
    author: &str,
    committer: &str,
) -> (Vec<u8>, Vec<u8>)

Raw author / committer header payloads for a new commit object.

When encoding is unset or UTF-8, returns empty vectors so crate::objects::serialize_commit writes the Unicode String fields as UTF-8. When encoding is non-UTF-8, encodes the full identity lines (name, email, timestamp) for storage in that charset.