fn metadata_byte(output_size: usize, operation_id: usize) -> u8 {
    ((output_size << 3) | operation_id) as u8
}
Generates the metadata byte for a given compression strategy.
The metadata byte is structured as:
First 5 bits: length of the compressed value
Last 3 bits: operation id corresponding to the given compression used.
core/lib/types/src/storage/writes/compression.rs