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+# Reminder Overlay Implementation Plan
+
+> **For Claude:** REQUIRED SUB-SKILL: Use superpowers:executing-plans to implement this plan task-by-task.
+
+**Goal:** 简化日历提醒机制，用 ReminderOverlay 统一处理所有用户交互，移除前台/后台判断逻辑。
+
+**Architecture:** 每条通知独立 payload，点击通知后打开 ReminderOverlay 处理用户操作（完成/稍后提醒）。同分钟多条通知按时间排序依次处理。操作完成后 app 退到后台。iOS 冷启动通过 UserDefaults 传递 payload，Android 使用 full-screen intent。
+
+**Tech Stack:** Flutter, flutter_local_notifications, Provider/Bloc (状态管理)
+
+---
+
+## Task 1: 创建 ReminderQueueManager
+
+**Files:**
+- Create: `apps/lib/features/calendar/reminders/reminder_queue_manager.dart`
+- Test: `apps/test/features/calendar/reminders/reminder_queue_manager_test.dart`
+
+**Step 1: 编写测试**
+
+```dart
+import 'package:flutter_test/flutter_test.dart';
+import 'package:social_app/features/calendar/reminders/reminder_queue_manager.dart';
+import 'package:social_app/features/calendar/reminders/models/reminder_payload.dart';
+
+void main() {
+  group('ReminderQueueManager', () {
+    test('按点击顺序处理，第一条处理完后处理剩余的按时间排序', () {
+      final manager = ReminderQueueManager();
+      
+      final event1 = ReminderPayload(eventId: '1', title: 'Event 1', startAt: DateTime(2026, 3, 20, 10, 1), mode: ReminderPayloadMode.single);
+      final event2 = ReminderPayload(eventId: '2', title: 'Event 2', startAt: DateTime(2026, 3, 20, 10, 2), mode: ReminderPayloadMode.single);
+      final event3 = ReminderPayload(eventId: '3', title: 'Event 3', startAt: DateTime(2026, 3, 20, 10, 3), mode: ReminderPayloadMode.single);
+      
+      // 用户点击 event2
+      manager.enqueueFromClick(event2);
+      // 剩余 event1 和 event3 按时间排序: event1 -> event3
+      manager.enqueuePending([event1, event3]);
+      
+      expect(manager.currentPayload?.eventId, '2');
+      manager.dequeueCurrent();
+      expect(manager.currentPayload?.eventId, '1');
+      manager.dequeueCurrent();
+      expect(manager.currentPayload?.eventId, '3');
+      manager.dequeueCurrent();
+      expect(manager.isEmpty, true);
+    });
+
+    test('单条通知处理完直接清空', () {
+      final manager = ReminderQueueManager();
+      final event = ReminderPayload(eventId: '1', title: 'Event 1', startAt: DateTime.now(), mode: ReminderPayloadMode.single);
+      
+      manager.enqueueFromClick(event);
+      expect(manager.isEmpty, false);
+      manager.dequeueCurrent();
+      expect(manager.isEmpty, true);
+    });
+  });
+}
+```
+
+**Step 2: 运行测试验证失败**
+
+Run: `cd apps && flutter test test/features/calendar/reminders/reminder_queue_manager_test.dart`
+Expected: FAIL - ReminderQueueManager not defined
+
+**Step 3: 编写最小实现**
+
+```dart
+import 'reminder_payload.dart';
+
+class ReminderQueueManager {
+  ReminderPayload? _currentPayload;
+  final List<ReminderPayload> _pending = [];
+
+  void enqueueFromClick(ReminderPayload payload) {
+    _currentPayload = payload;
+  }
+
+  void enqueuePending(List<ReminderPayload> payloads) {
+    payloads.sort((a, b) => a.startAt.compareTo(b.startAt));
+    _pending.addAll(payloads);
+  }
+
+  ReminderPayload? get currentPayload => _currentPayload;
+
+  bool get isEmpty => _currentPayload == null && _pending.isEmpty;
+
+  void dequeueCurrent() {
+    _currentPayload = null;
+    if (_pending.isNotEmpty) {
+      _currentPayload = _pending.removeAt(0);
+    }
+  }
+
+  void clear() {
+    _currentPayload = null;
+    _pending.clear();
+  }
+}
+```
+
+**Step 4: 运行测试验证通过**
+
+Run: `cd apps && flutter test test/features/calendar/reminders/reminder_queue_manager_test.dart`
+Expected: PASS
+
+**Step 5: 提交**
+
+```bash
+git add apps/lib/features/calendar/reminders/reminder_queue_manager.dart apps/test/features/calendar/reminders/reminder_queue_manager_test.dart
+git commit -m "feat(calendar): add ReminderQueueManager for handling multiple notifications"
+```
+
+---
+
+## Task 2: 创建 IOSNotificationPayloadBridge
+
+**Files:**
+- Create: `apps/lib/core/notifications/ios_notification_payload_bridge.dart`
+- Test: `apps/test/core/notifications/ios_notification_payload_bridge_test.dart`
+
+**Step 1: 编写测试**
+
+```dart
+import 'package:flutter_test/flutter_test.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+import 'package:social_app/core/notifications/ios_notification_payload_bridge.dart';
+import 'dart:convert';
+
+void main() {
+  group('IOSNotificationPayloadBridge', () {
+    test('启动时读取待处理的 notification payload', () async {
+      SharedPreferences.setMockInitialValues({
+        'pending_notification_payload': jsonEncode({
+          'eventId': 'evt_123',
+          'title': 'Test Event',
+          'startAt': '2026-03-20T10:00:00Z',
+          'mode': 'single',
+        }),
+      });
+      
+      final prefs = await SharedPreferences.getInstance();
+      final bridge = IOSNotificationPayloadBridge(prefs);
+      final payload = await bridge.getPendingPayload();
+      
+      expect(payload?.eventId, 'evt_123');
+      expect(payload?.title, 'Test Event');
+    });
+
+    test('处理完成后清理 UserDefaults', () async {
+      SharedPreferences.setMockInitialValues({
+        'pending_notification_payload': jsonEncode({
+          'eventId': 'evt_123',
+          'title': 'Test Event',
+          'startAt': '2026-03-20T10:00:00Z',
+          'mode': 'single',
+        }),
+      });
+      
+      final prefs = await SharedPreferences.getInstance();
+      final bridge = IOSNotificationPayloadBridge(prefs);
+      await bridge.clearPendingPayload();
+      
+      final remaining = prefs.getString('pending_notification_payload');
+      expect(remaining, isNull);
+    });
+  });
+}
+```
+
+**Step 2: 运行测试验证失败**
+
+Run: `cd apps && flutter test test/core/notifications/ios_notification_payload_bridge_test.dart`
+Expected: FAIL - IOSNotificationPayloadBridge not defined
+
+**Step 3: 编写最小实现**
+
+```dart
+import 'dart:convert';
+import 'package:shared_preferences/shared_preferences.dart';
+import '../../features/calendar/reminders/models/reminder_payload.dart';
+
+class IOSNotificationPayloadBridge {
+  static const String _key = 'pending_notification_payload';
+  final SharedPreferences _prefs;
+
+  IOSNotificationPayloadBridge(this._prefs);
+
+  Future<ReminderPayload?> getPendingPayload() async {
+    final raw = _prefs.getString(_key);
+    if (raw == null || raw.isEmpty) {
+      return null;
+    }
+    try {
+      final json = Map<String, dynamic>.from(jsonDecode(raw) as Map);
+      return ReminderPayload.fromJson(json);
+    } catch (_) {
+      return null;
+    }
+  }
+
+  Future<void> clearPendingPayload() async {
+    await _prefs.remove(_key);
+  }
+}
+```
+
+**Step 4: 运行测试验证通过**
+
+Run: `cd apps && flutter test test/core/notifications/ios_notification_payload_bridge_test.dart`
+Expected: PASS
+
+**Step 5: 提交**
+
+```bash
+git add apps/lib/core/notifications/ios_notification_payload_bridge.dart apps/test/core/notifications/ios_notification_payload_bridge_test.dart
+git commit -m "feat(notifications): add IOSNotificationPayloadBridge for cold start handling"
+```
+
+---
+
+## Task 3: 创建 ReminderOverlay UI 组件
+
+**Files:**
+- Create: `apps/lib/features/calendar/reminders/ui/reminder_overlay.dart`
+- Test: `apps/test/features/calendar/reminders/reminder_overlay_test.dart`
+
+**Step 1: 编写测试**
+
+```dart
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+import 'package:social_app/features/calendar/reminders/ui/reminder_overlay.dart';
+import 'package:social_app/features/calendar/reminders/reminder_queue_manager.dart';
+import 'package:social_app/core/notifications/local_notification_service.dart';
+import 'package:social_app/core/notifications/ios_notification_payload_bridge.dart';
+import 'package:social_app/features/calendar/data/services/calendar_service.dart';
+import 'package:social_app/features/calendar/reminders/reminder_queue_manager.dart';
+import 'package:social_app/features/calendar/reminders/models/reminder_payload.dart';
+
+void main() {
+  group('ReminderOverlay', () {
+    late ReminderQueueManager queueManager;
+    
+    setUp(() {
+      SharedPreferences.setMockInitialValues({});
+      queueManager = ReminderQueueManager();
+    });
+
+    testWidgets('显示日程标题和当前时间', (tester) async {
+      final payload = ReminderPayload(
+        eventId: '1',
+        title: 'Test Meeting',
+        startAt: DateTime(2026, 3, 20, 10, 0),
+        mode: ReminderPayloadMode.single,
+      );
+      queueManager.enqueueFromClick(payload);
+      
+      await tester.pumpWidget(
+        MaterialApp(
+          home: ReminderOverlay(
+            queueManager: queueManager,
+            onComplete: () {},
+            onSnooze: (minutes) {},
+            onArchive: () {},
+          ),
+        ),
+      );
+
+      expect(find.text('Test Meeting'), findsOneWidget);
+      // 当前时间显示在界面上
+      expect(find.textContaining(':'), findsWidgets);
+    });
+
+    testWidgets('点击完成按钮触发归档', (tester) async {
+      bool archiveCalled = false;
+      final payload = ReminderPayload(
+        eventId: '1',
+        title: 'Test Meeting',
+        startAt: DateTime(2026, 3, 20, 10, 0),
+        mode: ReminderPayloadMode.single,
+      );
+      queueManager.enqueueFromClick(payload);
+      
+      await tester.pumpWidget(
+        MaterialApp(
+          home: ReminderOverlay(
+            queueManager: queueManager,
+            onComplete: () {},
+            onSnooze: (minutes) {},
+            onArchive: () => archiveCalled = true,
+          ),
+        ),
+      );
+
+      await tester.tap(find.text('完成'));
+      await tester.pump();
+      
+      expect(archiveCalled, true);
+    });
+
+    testWidgets('点击稍后提醒显示下拉选项', (tester) async {
+      final payload = ReminderPayload(
+        eventId: '1',
+        title: 'Test Meeting',
+        startAt: DateTime(2026, 3, 20, 10, 0),
+        mode: ReminderPayloadMode.single,
+      );
+      queueManager.enqueueFromClick(payload);
+      
+      await tester.pumpWidget(
+        MaterialApp(
+          home: ReminderOverlay(
+            queueManager: queueManager,
+            onComplete: () {},
+            onSnooze: (minutes) {},
+            onArchive: () {},
+          ),
+        ),
+      );
+
+      await tester.tap(find.text('稍后提醒'));
+      await tester.pumpAndSettle();
+
+      expect(find.text('5 分钟'), findsOneWidget);
+      expect(find.text('15 分钟'), findsOneWidget);
+    });
+  });
+}
+```
+
+**Step 2: 运行测试验证失败**
+
+Run: `cd apps && flutter test test/features/calendar/reminders/reminder_overlay_test.dart`
+Expected: FAIL - ReminderOverlay not defined
+
+**Step 3: 编写最小实现**
+
+```dart
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:intl/intl.dart';
+import '../../../../core/theme/design_tokens.dart';
+import '../../../../shared/widgets/app_button.dart';
+import '../../reminders/reminder_queue_manager.dart';
+import '../../reminders/models/reminder_payload.dart';
+
+class ReminderOverlay extends StatefulWidget {
+  const ReminderOverlay({
+    super.key,
+    required this.queueManager,
+    required this.onComplete,
+    required this.onSnooze,
+    required this.onArchive,
+  });
+
+  final ReminderQueueManager queueManager;
+  final VoidCallback onComplete;
+  final void Function(int minutes) onSnooze;
+  final VoidCallback onArchive;
+
+  @override
+  State<ReminderOverlay> createState() => _ReminderOverlayState();
+}
+
+class _ReminderOverlayState extends State<ReminderOverlay> {
+  bool _showSnoozeOptions = false;
+  final LayerLink _layerLink = LayerLink();
+  OverlayEntry? _overlayEntry;
+
+  ReminderPayload? get _currentPayload => widget.queueManager.currentPayload;
+
+  @override
+  void dispose() {
+    _hideSnoozeOptions();
+    super.dispose();
+  }
+
+  void _hideSnoozeOptions() {
+    _overlayEntry?.remove();
+    _overlayEntry = null;
+    setState(() {
+      _showSnoozeOptions = false;
+    });
+  }
+
+  void _showSnoozeDropdown() {
+    _hideSnoozeOptions();
+    
+    _overlayEntry = OverlayEntry(
+      builder: (context) => Positioned(
+        width: 120,
+        child: Material(
+          elevation: 4,
+          borderRadius: BorderRadius.circular(AppRadius.md),
+          child: Container(
+            decoration: BoxDecoration(
+              color: AppColors.white,
+              borderRadius: BorderRadius.circular(AppRadius.md),
+              border: Border.all(color: AppColors.borderSecondary),
+            ),
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              children: [
+                _SnoozeOption(
+                  label: '5 分钟',
+                  onTap: () {
+                    _hideSnoozeOptions();
+                    widget.onSnooze(5);
+                  },
+                ),
+                Divider(height: 1, color: AppColors.borderSecondary),
+                _SnoozeOption(
+                  label: '15 分钟',
+                  onTap: () {
+                    _hideSnoozeOptions();
+                    widget.onSnooze(15);
+                  },
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+    
+    Overlay.of(context).insert(_overlayEntry!);
+    setState(() {
+      _showSnoozeOptions = true;
+    });
+  }
+
+  void _handleComplete() {
+    widget.onArchive();
+    widget.queueManager.dequeueCurrent();
+    if (!widget.queueManager.isEmpty) {
+      // 下一条会通过外部状态管理打开新的 overlay
+    }
+    widget.onComplete();
+  }
+
+  void _handleSnooze(int minutes) {
+    widget.onSnooze(minutes);
+    widget.queueManager.dequeueCurrent();
+    if (!widget.queueManager.isEmpty) {
+      // 下一条会通过外部状态管理打开新的 overlay
+    }
+    widget.onComplete();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final payload = _currentPayload;
+    if (payload == null) {
+      return const SizedBox.shrink();
+    }
+
+    return Container(
+      color: AppColors.white,
+      child: SafeArea(
+        child: Padding(
+          padding: const EdgeInsets.all(AppSpacing.lg),
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            children: [
+              Text(
+                payload.title,
+                style: Theme.of(context).textTheme.headlineSmall?.copyWith(
+                  color: AppColors.slate900,
+                  fontWeight: FontWeight.w600,
+                ),
+                textAlign: TextAlign.center,
+              ),
+              const SizedBox(height: AppSpacing.sm),
+              Text(
+                DateFormat('HH:mm').format(DateTime.now()),
+                style: Theme.of(context).textTheme.titleLarge?.copyWith(
+                  color: AppColors.slate500,
+                ),
+                textAlign: TextAlign.center,
+              ),
+              const SizedBox(height: AppSpacing.xl),
+              Row(
+                children: [
+                  Expanded(
+                    child: CompositedTransformTarget(
+                      link: _layerLink,
+                      child: AppButton(
+                        text: '稍后提醒',
+                        isOutlined: true,
+                        onPressed: _showSnoozeDropdown,
+                      ),
+                    ),
+                  ),
+                  const SizedBox(width: AppSpacing.md),
+                  Expanded(
+                    child: AppButton(
+                      text: '完成',
+                      onPressed: _handleComplete,
+                    ),
+                  ),
+                ],
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class _SnoozeOption extends StatelessWidget {
+  const _SnoozeOption({
+    required this.label,
+    required this.onTap,
+  });
+
+  final String label;
+  final VoidCallback onTap;
+
+  @override
+  Widget build(BuildContext context) {
+    return InkWell(
+      onTap: onTap,
+      child: Padding(
+        padding: const EdgeInsets.symmetric(
+          horizontal: AppSpacing.md,
+          vertical: AppSpacing.sm,
+        ),
+        child: Text(
+          label,
+          style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+            color: AppColors.slate900,
+          ),
+        ),
+      ),
+    );
+  }
+}
+```
+
+**Step 4: 运行测试验证通过**
+
+Run: `cd apps && flutter test test/features/calendar/reminders/reminder_overlay_test.dart`
+Expected: PASS
+
+**Step 5: 提交**
+
+```bash
+git add apps/lib/features/calendar/reminders/ui/reminder_overlay.dart apps/test/features/calendar/reminders/reminder_overlay_test.dart
+git commit -m "feat(calendar): add ReminderOverlay UI component"
+```
+
+---
+
+## Task 4: 修改 LocalNotificationService - 移除权限降级逻辑
+
+**Files:**
+- Modify: `apps/lib/core/notifications/local_notification_service.dart`
+
+**Step 1: 阅读现有代码确认移除范围**
+
+Read: `apps/lib/core/notifications/local_notification_service.dart`
+
+**Step 2: 移除以下逻辑**
+
+1. 移除 `_canDeliverSystemNotification` 相关判断
+2. 移除 `_scheduleInAppFallbackRemindersFrom` 方法
+3. 移除 `_scheduleInAppFallbackPayload` 方法
+4. 移除 `_inAppFallbackTimersByEventId` 及相关方法
+5. 移除 `_trackFallback` 方法
+6. 移除 `rebuildUpcomingReminders` 中的降级分支
+
+**Step 3: 验证 flutter analyze 通过**
+
+Run: `cd apps && flutter analyze lib/core/notifications/local_notification_service.dart`
+Expected: 无错误
+
+**Step 4: 提交**
+
+```bash
+git add apps/lib/core/notifications/local_notification_service.dart
+git commit -m "refactor(notifications): remove permission fallback logic"
+```
+
+---
+
+## Task 5: 修改通知发送逻辑 - 使用原生分组
+
+**Files:**
+- Modify: `apps/lib/core/notifications/local_notification_service.dart`
+
+**Step 1: 添加 threadIdentifier/groupKey 到通知详情**
+
+在 `_buildNotificationDetails` 方法中：
+- iOS: 添加 `threadIdentifier: _getThreadIdentifier(fireAt)`
+- Android: 添加 `groupKey: _getGroupKey(fireAt)`
+
+**Step 2: 实现分组 key 方法**
+
+```dart
+String _getThreadIdentifier(DateTime fireAt) {
+  final bucket = fireAt.millisecondsSinceEpoch ~/ const Duration(minutes: 1).inMilliseconds;
+  return 'calendar_reminder_$bucket';
+}
+
+String _getGroupKey(DateTime fireAt) {
+  final bucket = fireAt.millisecondsSinceEpoch ~/ const Duration(minutes: 1).inMilliseconds;
+  return 'com.socialapp.calendar.$bucket';
+}
+```
+
+**Step 3: 验证 flutter analyze 通过**
+
+Run: `cd apps && flutter analyze lib/core/notifications/local_notification_service.dart`
+Expected: 无错误
+
+**Step 4: 提交**
+
+```bash
+git add apps/lib/core/notifications/local_notification_service.dart
+git commit -m "feat(notifications): add native notification grouping by time bucket"
+```
+
+---
+
+## Task 6: 修改 main.dart - 集成 iOS payload bridge
+
+**Files:**
+- Modify: `apps/lib/main.dart`
+
+**Step 1: 在 main() 中添加启动时检查**
+
+在 `runApp` 之前或 app 初始化时：
+1. 创建 IOSNotificationPayloadBridge 实例
+2. 调用 `getPendingPayload()`
+3. 如果有 payload，通过 ReminderQueueManager 处理
+
+**Step 2: 验证 flutter analyze 通过**
+
+Run: `cd apps && flutter analyze lib/main.dart`
+Expected: 无错误
+
+**Step 3: 提交**
+
+```bash
+git add apps/lib/main.dart
+git commit -m "feat(ios): integrate IOSNotificationPayloadBridge for cold start handling"
+```
+
+---
+
+## Task 7: 删除废弃组件
+
+**Files:**
+- Delete: `apps/lib/features/calendar/reminders/reminder_cold_start_queue.dart`
+- Delete: `apps/lib/features/calendar/reminders/reminder_outbox_store.dart`
+- Delete: `apps/lib/features/calendar/reminders/reminder_action_dedupe_store.dart`
+- Delete: `apps/lib/features/calendar/reminders/reminder_overlap_policy.dart`
+- Delete: `apps/lib/features/calendar/reminders/ui/reminder_foreground_presenter.dart`
+- Delete: `apps/lib/features/calendar/reminders/ui/reminder_presentation_coordinator.dart`
+- Delete: `apps/lib/features/calendar/reminders/ui/widgets/reminder_action_sheet.dart`
+
+**Step 1: 删除文件**
+
+```bash
+git rm apps/lib/features/calendar/reminders/reminder_cold_start_queue.dart
+git rm apps/lib/features/calendar/reminders/reminder_outbox_store.dart
+git rm apps/lib/features/calendar/reminders/reminder_action_dedupe_store.dart
+git rm apps/lib/features/calendar/reminders/reminder_overlap_policy.dart
+git rm apps/lib/features/calendar/reminders/ui/reminder_foreground_presenter.dart
+git rm apps/lib/features/calendar/reminders/ui/reminder_presentation_coordinator.dart
+git rm apps/lib/features/calendar/reminders/ui/widgets/reminder_action_sheet.dart
+```
+
+**Step 2: 删除测试文件**
+
+```bash
+git rm apps/test/features/calendar/reminders/reminder_cold_start_queue_test.dart
+git rm apps/test/features/calendar/reminders/reminder_outbox_store_test.dart
+git rm apps/test/features/calendar/reminders/reminder_action_dedupe_store_test.dart
+git rm apps/test/features/calendar/reminders/reminder_overlap_policy_test.dart
+git rm apps/test/features/calendar/reminders/reminder_foreground_presenter_test.dart
+git rm apps/test/features/calendar/reminders/reminder_presentation_coordinator_test.dart
+git rm apps/test/features/calendar/reminders/reminder_action_sheet_test.dart
+```
+
+**Step 3: 运行 flutter analyze 验证无引用错误**
+
+Run: `cd apps && flutter analyze`
+Expected: 无错误（可能有 deprecated warnings 可以忽略）
+
+**Step 4: 提交**
+
+```bash
+git commit -m "refactor(calendar): remove deprecated reminder components"
+```
+
+---
+
+## Task 8: iOS 原生层配置 (AppDelegate.swift)
+
+**Files:**
+- Modify: `apps/ios/Runner/AppDelegate.swift`
+
+**Step 1: 添加 UserDefaults 写入逻辑**
+
+在 `userNotificationCenter(_, didReceive, withCompletionHandler)` 中：
+1. 获取 notification 的 `userInfo`
+2. 将 payload 写入 `UserDefaults.standard`
+3. Key: `pending_notification_payload`
+
+**Step 2: 验证 Xcode build**
+
+Run: `cd apps && flutter build ios --simulator --no-codesign 2>&1 | head -50`
+Expected: Build 成功
+
+**Step 3: 提交**
+
+```bash
+git add apps/ios/Runner/AppDelegate.swift
+git commit -m "feat(ios): write notification payload to UserDefaults on cold start"
+```
+
+---
+
+## 验证清单
+
+完成所有任务后，运行以下验证：
+
+```bash
+# 1. Flutter analyze
+cd apps && flutter analyze
+
+# 2. 测试
+cd apps && flutter test test/features/calendar/reminders/
+
+# 3. iOS build
+cd apps && flutter build ios --simulator --no-codesign
+
+# 4. Android build  
+cd apps && flutter build apk --debug
+```
+
+---
+
+## Plan Complete
+
+**Plan saved to:** `docs/plans/2026-03-20-reminder-overlay-implementation-plan.md`
+
+**Two execution options:**
+
+**1. Subagent-Driven (this session)** - I dispatch fresh subagent per task, review between tasks, fast iteration
+
+**2. Parallel Session (separate)** - Open new session with executing-plans, batch execution with checkpoints
+
+**Which approach?**