Function byte_aligned_bitwise_unary_op_helper 

fn byte_aligned_bitwise_unary_op_helper<F>(
    buffer: &mut [u8],
    offset_in_bits: usize,
    len_in_bits: usize,
    op: F,
)
where
    F: FnMut(u64) -> u64,

Perform bitwise unary operation on byte-aligned buffer.

This is the optimized path for byte-aligned unary operations. It processes data in u64 chunks for maximum efficiency, then handles any remainder bits.

Arguments

• buffer - The mutable buffer (must be byte-aligned)
• offset_in_bits - Starting bit offset (must be multiple of 8)
• len_in_bits - Number of bits to process
• op - Unary operation to apply (e.g., |a| !a)