Function work 

pub async fn work(
    data: &[u8],
    salt: Option<&[u8]>,
    opts: WorkOptions,
) -> Result<String, SeaError>

Compute proof-of-work or content hash.

PBKDF2 Mode (default)

• Algorithm: PBKDF2-HMAC-SHA256
• Iterations: 100,000 (configurable via WorkOptions::iterations)
• Salt: random 9 bytes if not provided (matching Gun.js)
• Output: base64-encoded derived key

SHA-256 Mode

• Triggered when WorkOptions::name starts with "sha" (case-insensitive)
• Direct SHA-256 hash of input data
• Output: base64-encoded hash

Arguments

• data — Input bytes to hash
• salt — Optional salt (PBKDF2 mode only). If None, uses WorkOptions::salt or generates a random 9-byte salt.
• opts — Configuration (see WorkOptions)

Errors

Returns SeaError::Crypto on task join failure or internal error.