Secure credentials encoding issue on Mac

[snowbagoly]

Thanks for implementing this library, it's really useful! 🎉

I have bumped into a small issue while using it on Mac: if the username or the password contains any special characters, they are not stored and retrieved correctly. E.g. if I store the username "täst", it retrieves this string: 0x74C3A47374 "t\303\244st

My macOS version is Sonoma 14.0.

Here is the code that I use to store the credentials:

fun storeAccount(accountKey: String, urlKey: String, settings: ServerConfiguration) {
    val credentialStorage = StorageProvider.getCredentialStorage(true, StorageProvider.SecureOption.REQUIRED)
    val storedSettings = Settings()

    if (settings.url.isEmpty()) {
        storedSettings.remove(urlKey)
        credentialStorage.delete(accountKey)
        return
    }

    storedSettings.putString(urlKey, settings.url)
    if (settings.username.isEmpty()) {
        credentialStorage.delete(accountKey)
        return
    }

    val credentialsToStore = StoredCredential(settings.username, settings.password.toCharArray())
    credentialStorage.add(accountKey, credentialsToStore)
}

This is used to load them:

fun getAccount(accountKey: String, urlKey: String): ServerConfiguration {
    val storedSettings = Settings()
    val url = storedSettings.getString(urlKey, "")
    val credentialStorage = StorageProvider.getCredentialStorage(true, StorageProvider.SecureOption.REQUIRED)
    val credential: StoredCredential? = credentialStorage.get(accountKey)
    val username = credential?.username ?: ""
    val password = (credential?.password ?: CharArray(0)).joinToString("")
    return ServerConfiguration(url, username, password)
}

I also tested on Windows and there it worked without issues. (Not sure about Linux as I didn't manage to get it running at all due to some strange NPEs, I'm still looking into that.)