feat(useragent): bootstrap / unseal flow implementattion

useragent/lib/providers/evm.dart

@@ -0,0 +1,23 @@
+import 'package:arbiter/proto/evm.pb.dart';
+import 'package:arbiter/proto/user_agent.pb.dart';
+import 'package:arbiter/providers/connection/connection_manager.dart';
+import 'package:protobuf/well_known_types/google/protobuf/empty.pb.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+part 'evm.g.dart';
+
+@riverpod
+class Evm extends _$Evm {
+  Future<List<WalletEntry>?> build() async {
+    final connection = await ref.watch(connectionManagerProvider.future);
+    if (connection == null) {
+      return null;
+    }
+
+    await connection.send(UserAgentRequest(
+      evmWalletList: Empty()
+    ));
+
+    final response = await connection.receive();
+  }
+}