added pagination

lib/components/utils/debounce.dart

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+import 'dart:async';
+import 'dart:ui';
+
+class Debounce {
+  factory Debounce() => _instance;
+
+  Debounce._();
+
+  static final Debounce _instance = Debounce._();
+
+  static Timer? _timer;
+
+  static void run(
+      VoidCallback action,
+      {Duration delay = const Duration(milliseconds: 500)}
+  ) {
+    _timer?.cancel();
+    _timer = Timer(delay, action);
+  }
+}

lib/components/utils/error_callback.dart

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+typedef OnErrorCallback = void Function(String? error);