Function encode_delta_large 

pub fn encode_delta_large(
    commands: &[PlacedCommand],
    inplace: bool,
    version_size: usize,
    src_crc: &[u8; 8],
    dst_crc: &[u8; 8],
    force_large: bool,
) -> Vec<u8> 

Encode placed commands to the DLT\x04 binary delta format.

DLT\x04 header: magic(4) + flags(1) + version_size(u64 BE) + crcs(16) = 29 bytes. Commands: per-command size selection — COPY(1)/BIGCOPY(3), ADD(2)/BIGADD(4), MOVE(5)/BIGMOVE(6). Small variants use u32 fields; big variants use u64 fields. Fields ≤ U32_MAX get the small variant; larger fields get the big variant.

This function is infallible: usize → u64 is a widening conversion on all platforms Rust supports (Rust guarantees usize ≤ 64 bits), so no field can overflow a u64. Contrast with encode_delta (DLT\x03), which returns Result because usize → u32 truncates on 64-bit platforms.