feat(useragent): added connection info setup screen

useragent/lib/providers/server_info.dart

@@ -0,0 +1,51 @@
+import 'package:arbiter/features/server_info_storage.dart';
+import 'package:cryptography/cryptography.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+part 'server_info.g.dart';
+
+@riverpod
+ServerInfoStorage serverInfoStorage(Ref ref) {
+  return const SecureServerInfoStorage();
+}
+
+@Riverpod(keepAlive: true)
+class ServerInfo extends _$ServerInfo {
+  @override
+  Future<StoredServerInfo?> build() {
+    final storage = ref.watch(serverInfoStorageProvider);
+    return storage.load();
+  }
+
+  Future<void> save({
+    required String address,
+    required int port,
+    required List<int> caCert,
+  }) async {
+    final storage = ref.read(serverInfoStorageProvider);
+    final fingerprint = await _fingerprint(caCert);
+    final serverInfo = StoredServerInfo(
+      address: address,
+      port: port,
+      caCertFingerprint: fingerprint,
+    );
+
+    state = await AsyncValue.guard(() async {
+      await storage.save(serverInfo);
+      return serverInfo;
+    });
+  }
+
+  Future<void> clear() async {
+    final storage = ref.read(serverInfoStorageProvider);
+    state = await AsyncValue.guard(() async {
+      await storage.clear();
+      return null;
+    });
+  }
+
+  Future<String> _fingerprint(List<int> caCert) async {
+    final digest = await Sha256().hash(caCert);
+    return digest.bytes.map((byte) => byte.toRadixString(16).padLeft(2, '0')).join();
+  }
+}

useragent/lib/providers/server_info.g.dart

@@ -0,0 +1,102 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'server_info.dart';
+
+// **************************************************************************
+// RiverpodGenerator
+// **************************************************************************
+
+// GENERATED CODE - DO NOT MODIFY BY HAND
+// ignore_for_file: type=lint, type=warning
+
+@ProviderFor(serverInfoStorage)
+final serverInfoStorageProvider = ServerInfoStorageProvider._();
+
+final class ServerInfoStorageProvider
+    extends
+        $FunctionalProvider<
+          ServerInfoStorage,
+          ServerInfoStorage,
+          ServerInfoStorage
+        >
+    with $Provider<ServerInfoStorage> {
+  ServerInfoStorageProvider._()
+    : super(
+        from: null,
+        argument: null,
+        retry: null,
+        name: r'serverInfoStorageProvider',
+        isAutoDispose: true,
+        dependencies: null,
+        $allTransitiveDependencies: null,
+      );
+
+  @override
+  String debugGetCreateSourceHash() => _$serverInfoStorageHash();
+
+  @$internal
+  @override
+  $ProviderElement<ServerInfoStorage> $createElement(
+    $ProviderPointer pointer,
+  ) => $ProviderElement(pointer);
+
+  @override
+  ServerInfoStorage create(Ref ref) {
+    return serverInfoStorage(ref);
+  }
+
+  /// {@macro riverpod.override_with_value}
+  Override overrideWithValue(ServerInfoStorage value) {
+    return $ProviderOverride(
+      origin: this,
+      providerOverride: $SyncValueProvider<ServerInfoStorage>(value),
+    );
+  }
+}
+
+String _$serverInfoStorageHash() => r'fc06865e7314b1a2493c5de1a9347923a3d21c5c';
+
+@ProviderFor(ServerInfo)
+final serverInfoProvider = ServerInfoProvider._();
+
+final class ServerInfoProvider
+    extends $AsyncNotifierProvider<ServerInfo, StoredServerInfo?> {
+  ServerInfoProvider._()
+    : super(
+        from: null,
+        argument: null,
+        retry: null,
+        name: r'serverInfoProvider',
+        isAutoDispose: false,
+        dependencies: null,
+        $allTransitiveDependencies: null,
+      );
+
+  @override
+  String debugGetCreateSourceHash() => _$serverInfoHash();
+
+  @$internal
+  @override
+  ServerInfo create() => ServerInfo();
+}
+
+String _$serverInfoHash() => r'6e94f52de03259695a2166b766004eec60ff45fa';
+
+abstract class _$ServerInfo extends $AsyncNotifier<StoredServerInfo?> {
+  FutureOr<StoredServerInfo?> build();
+  @$mustCallSuper
+  @override
+  void runBuild() {
+    final ref =
+        this.ref as $Ref<AsyncValue<StoredServerInfo?>, StoredServerInfo?>;
+    final element =
+        ref.element
+            as $ClassProviderElement<
+              AnyNotifier<AsyncValue<StoredServerInfo?>, StoredServerInfo?>,
+              AsyncValue<StoredServerInfo?>,
+              Object?,
+              Object?
+            >;
+    element.handleCreate(ref, build);
+  }
+}