forAuth static method
The connection a request under auth must use towards url (NIP-42).
Null means no connection can satisfy it and nothing may be sent to that
relay: falling back to the anonymous one is exactly what the caller ruled
out. A null auth keeps the historical default.
Implementation
static RelayConnectionKey? forAuth(String url, AuthPolicy? auth) =>
switch (auth) {
AuthPolicyRequire(:final account) => account.signer.canSign()
? RelayConnectionKey.authenticated(url, account.pubkey)
: null,
null ||
AuthPolicyNever() ||
AuthPolicyAllow() =>
RelayConnectionKey.anonymous(url),
};