Bugfix: Transactions signing (#14)

The previous transaction signing system used SIGN_MODE_AMINO_JSON, which is deprecated and no longer supported on the SEKAI side. This branch introduces a new way to sign transactions that use SIGN_MODE_DIRECT mode.

List of changes:
- imported "cryptography_utils" package which contains crypto-algorithms required to build and sign Cosmos transactions
- removed classes from "infra/dto/api_kira/broadcast/request/transaction/components" as they are included in the “cryptography_utils” package and are no longer needed on the miro side
- modified classes from "infra/dto/shared/messages" to extend "ProtobufAny" class from "cryptography_utils" package and define protobuf serialization for Cosmos messages
- replaced Uint8List private key in wallet.dart with ECPrivateKey from "cryptography_utils" package to simplify accessing private key for transaction signing
- removed signature_utils.dart and sign() method from tx_utils.dart, as now signing functionality is handled by the external package
- created new sign() method in unsigned_tx_model.dart, which calls proper signing method from "cryptography_utils" package
- removed Wallet.fromKeyfileData() constructor from wallet.dart as it wasn't used anywhere but needed improvement after changes
- adjusted tests and classes where updated classes were used

.gitignore

@@ -1,5 +1,9 @@
-#FVM sdk ignore
+# Flutter Version Management
 .fvm/flutter_sdk
+.fvm/versions
+.fvm/version
+.fvm/release
+.fvmrc
 
 # Miscellaneous
 *.class

lib/blocs/pages/drawer/create_wallet_drawer_page/create_wallet_drawer_page_cubit.dart

@@ -24,7 +24,7 @@ class CreateWalletDrawerPageCubit extends Cubit<ACreateWalletDrawerPageState> {
     emit(CreateWalletDrawerPageLoadingState());
     await Future<void>.delayed(const Duration(milliseconds: 500));
     Mnemonic mnemonic = Mnemonic.random();
-    Wallet wallet = Wallet.derive(mnemonic: mnemonic);
+    Wallet wallet = await Wallet.derive(mnemonic: mnemonic);
 
     emit(CreateWalletDrawerPageLoadedState(mnemonic: mnemonic, wallet: wallet));
   }

lib/blocs/pages/transactions/tx_process_cubit/tx_process_cubit.dart

@@ -20,7 +20,6 @@ import 'package:miro/shared/models/transactions/signed_transaction_model.dart';
 import 'package:miro/shared/models/transactions/unsigned_tx_model.dart';
 import 'package:miro/shared/models/wallet/wallet.dart';
 import 'package:miro/shared/utils/logger/app_logger.dart';
-import 'package:miro/shared/utils/transactions/tx_utils.dart';
 
 class TxProcessCubit<T extends AMsgFormModel> extends Cubit<ATxProcessState> {
   final AuthCubit authCubit = globalLocator<AuthCubit>();
@@ -128,8 +127,6 @@ class TxProcessCubit<T extends AMsgFormModel> extends Cubit<ATxProcessState> {
     if (wallet == null) {
       throw Exception('Wallet cannot be null when signing transaction');
     }
-    SignedTxModel signedTxModel = TxUtils.sign(unsignedTxModel: unsignedTxModel, wallet: wallet);
-    await Future<void>.delayed(const Duration(milliseconds: 100));
-    return signedTxModel;
+    return unsignedTxModel.sign(wallet);
   }
 }

lib/infra/dto/api_kira/broadcast/request/broadcast_req.dart

@@ -1,8 +1,8 @@
+import 'package:cryptography_utils/cryptography_utils.dart';
 import 'package:equatable/equatable.dart';
-import 'package:miro/infra/dto/api_kira/broadcast/request/transaction/tx.dart';
 
 class BroadcastReq extends Equatable {
-  final Tx tx;
+  final CosmosTx tx;
   final String mode;
 
   const BroadcastReq({
@@ -12,7 +12,7 @@ class BroadcastReq extends Equatable {
 
   Map<String, dynamic> toJson() {
     return <String, dynamic>{
-      'tx': tx.toJson(),
+      'tx': tx.toProtoJson(),
       'mode': mode,
     };
   }