wcVerifyJwt function
Verify a relay-auth JWT against the public key embedded in its iss claim.
Implementation
bool wcVerifyJwt(String jwt) {
final parts = jwt.split('.');
if (parts.length != 3) return false;
final data = '${parts[0]}.${parts[1]}';
final sig = _b64UrlDecode(parts[2]);
final payload =
jsonDecode(utf8.decode(_b64UrlDecode(parts[1]))) as Map<String, dynamic>;
final pub = wcDecodeIss(payload['iss'] as String);
return ed25519Verify(pub, Uint8List.fromList(utf8.encode(data)), sig);
}