Function set_bit_lsb 

pub fn set_bit_lsb(
    segment: &mut [u8],
    bit_offset_in_segment: usize,
    bit: u8,
) -> u8

Sets bit value in segment using LSB order, returning old bit (aligned with Kvrocks SetBitTo). 设置分段中指定位的值（LSB 顺序，返回原位值，对标 Apache Kvrocks util::lsb::SetBitTo）