# Functions
New returns a new Hasher for creating and validating signed tokens.
WithHash can be used to change the hash function.
WithKey uses a fixed key for signing and verification.
WithKeyFromLambdaExtensionSecrets retrieves key from AWS Parameters and Secrets Lambda Extension (https://docs.aws.amazon.com/secretsmanager/latest/userguide/retrieving-secrets_lambda.html) using the default client [lambda.DefaultParameterSecretsExtensionClient].
WithKeyFromSecretsManager retrieves key from AWS Secrets Hasher.
# Interfaces
Hasher provides HMAC signing and validation methods.
# Type aliases
KeyProvider customises how the Hasher retrieves its key.
Option customises other aspects of Hasher.