Function deck_to_entropy 

pub fn deck_to_entropy<const CARDS: u8, const N: usize>(
    cards: &[u8],
) -> Result<DeckEntropy<CARDS, N>, EntropyError>

Fold a sequence of drawn cards into an N-byte entropy buffer.

Cards are formatted as decimal indices, hyphen-separated, SHA-256 hashed, then truncated to N bytes. Mirrors Krux’s d20 string shape ("-".join) for multi-digit values.

Example

use kdk_entropy::{deck_to_entropy, DeckEntropy};
use kdk_zeroize::prelude::*;

// SHA-256("0-1-2-3-...-24")[:16].
let cards: [u8; 25] = [
    0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
    10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
    20, 21, 22, 23, 24,
];
let e: DeckEntropy<52, 16> = deck_to_entropy(&cards).unwrap();
assert_eq!(
    e.expose_secret(),
    &[
        0x92, 0xe2, 0x92, 0xe3, 0x4c, 0x44, 0x48, 0xc1,
        0x57, 0x73, 0x1a, 0xff, 0x3d, 0x40, 0x10, 0x38,
    ]
);