fix: Use single-isolate push

lib/utils/fluffy_client.dart

@@ -0,0 +1,34 @@
+import 'package:famedlysdk/famedlysdk.dart';
+import 'package:famedlysdk/encryption.dart';
+import 'platform_infos.dart';
+import 'famedlysdk_store.dart';
+
+class FluffyClient extends Client {
+  static final FluffyClient _instance = FluffyClient._internal();
+
+  /// The ID of the currently active room, if there is one. May be null or emtpy
+  String activeRoomId;
+
+  factory FluffyClient() {
+    return _instance;
+  }
+
+  FluffyClient._internal()
+      : super(
+          PlatformInfos.clientName,
+          enableE2eeRecovery: true,
+          verificationMethods: {
+            KeyVerificationMethod.numbers,
+            if (PlatformInfos.isMobile || PlatformInfos.isLinux)
+              KeyVerificationMethod.emoji,
+          },
+          importantStateEvents: <String>{
+            'im.ponies.room_emotes', // we want emotes to work properly
+          },
+          databaseBuilder: getDatabase,
+          supportedLoginTypes: {
+            AuthenticationTypes.password,
+            if (PlatformInfos.isMobile) AuthenticationTypes.sso
+          },
+        );
+}