Initial date planner app (#2390)

Initial **experimental** date planner iOS sample.

## Pre-launch Checklist

- [x] I read the [Flutter Style Guide] _recently_, and have followed its
advice.
- [x] I signed the [CLA].
- [x] I read the [Contributors Guide].
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-devrel
channel on [Discord].

<!-- Links -->
[Flutter Style Guide]:
https://github.com/flutter/flutter/blob/master/docs/contributing/Style-guide-for-Flutter-repo.md
[CLA]: https://cla.developers.google.com/
[Discord]:
https://github.com/flutter/flutter/blob/master/docs/contributing/Chat.md
[Contributors Guide]:
https://github.com/flutter/samples/blob/main/CONTRIBUTING.md

experimental/date_planner/lib/event_row.dart

@@ -0,0 +1,52 @@
+// Copyright 2024 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:flutter/cupertino.dart';
+
+import 'event.dart';
+
+class EventRow extends StatelessWidget {
+  const EventRow({
+    super.key,
+    required this.event,
+    this.onTap,
+  });
+
+  final Event event;
+  final FutureOr<void> Function()? onTap;
+
+  @override
+  Widget build(BuildContext context) {
+    // TODO(mit-mit): The corners of the tiles should be rounded.
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 4),
+      child: CupertinoListTile(
+        title: Text(
+          event.title,
+          style: const TextStyle(fontWeight: FontWeight.bold),
+        ),
+        subtitle: Text(event.dateFormated),
+        leading: Icon(
+          event.icon,
+          size: 28,
+          color: event.color.color,
+        ),
+        trailing: Row(
+          children: [
+            event.isComplete
+                ? const Icon(CupertinoIcons.check_mark)
+                : Text(
+                    '${event.remainingTaskCount}',
+                    style: const TextStyle(color: CupertinoColors.systemGrey),
+                  ),
+            const CupertinoListTileChevron(),
+          ],
+        ),
+        onTap: onTap,
+      ),
+    );
+  }
+}