Function extract_ogg_bytes 

pub fn extract_ogg_bytes(
    input: impl AsRef<Path>,
    entry_idx: Option<usize>,
) -> Result<(Vec<u8>, String)>

Extract raw Ogg bytes from Siglus containers.

• .ovk: extracts the Ogg segment at entry_idx.
• .owp: decrypts the whole file to raw Ogg.