Function encode_ht_code_block_scalar_with_passes 

pub fn encode_ht_code_block_scalar_with_passes(
    coefficients: &[i32],
    width: u32,
    height: u32,
    total_bitplanes: u8,
    target_coding_passes: u8,
) -> Result<EncodedHtJ2kCodeBlock, &'static str>

Adapter scalar HTJ2K encoder helper with an explicit coding-pass request.