opt: auto rm pwd in key page for safe

lib/core/utils/server.dart

@@ -8,12 +8,22 @@ import '../../data/store/private_key.dart';
 import '../../locator.dart';
 
 /// Must put this func out of any Class.
+/// 
 /// Because of this function is called by [compute] in [ServerProvider.genClient].
+/// 
 /// https://stackoverflow.com/questions/51998995/invalid-arguments-illegal-argument-in-isolate-message-object-is-a-closure
 List<SSHKeyPair> loadIndentity(String key) {
   return SSHKeyPair.fromPem(key);
 }
 
+/// [args] : [key, pwd]
+String decyptPem(List<String> args) {
+  /// skip when the key is not encrypted, or will throw exception
+  if (!SSHKeyPair.isEncryptedPem(args[0])) return args[0];
+  final sshKey = SSHKeyPair.fromPem(args[0], args[1]);
+  return sshKey.first.toPem();
+}
+
 Future<SSHClient> genClient(ServerPrivateInfo spi) async {
   final socket = await SSHSocket.connect(
     spi.ip,