Feature Request: Add Native App Shortcuts (Quick Actions) for Add Task & Reports

### Describe your improvement idea or feature request

To improve user experience and navigation speed, we should add native home screen **App Shortcuts** (the quick actions menu that appears when a user long-presses the app icon).

Specifically, we need to add two quick actions:
1. **Add Task:** Instantly opens the app and triggers the `AddTaskSheet` bottom sheet.
2. **Reports Page:** Opens the app and routes the user directly to the Reports dashboard.

### How would you like to see it implemented?

This should be implemented using the official [`quick_actions`](https://pub.dev/packages/quick_actions) Flutter package, integrated cleanly with our GetX architecture.

**1. Controller Logic:** Create a dedicated GetX controller (e.g., `AppShortcutController`) initialized in `onReady()` to handle the shortcut listeners. This prevents race conditions during the app's boot sequence and keeps `main.dart` clean.

**2. Routing Details:**
- Wire the `add_task` action to `Get.bottomSheet(AddTaskSheet())`.
- Wire the `reports` action to `Get.toNamed('/reports')`.

### Put here any screenshots or videos (optional)

_No response_

### How can we contact you (optional)

You can tag me right here on GitHub, or reach me on Zulip (User ID: 1017036).

### Would you like to work on this issue?

Yes

### By submitting this issue, I have confirmed that:

- [x] I have starred the repo ⭐ and watched 👀 it on GitHub and followed the contribution guidelines.

アプリの起動フロー、GetX コントローラー、AddTaskSheet、および '/reports' ルートを特定します。まず、onReady() でコントローラーがどのように初期化されているか、また現在ナビゲーションがどのように接続されているかを確認します。quick_actions リスナーを統合し、add_task で AddTaskSheet を開き、reports で '/reports' に遷移するようにしてから、ネイティブアプリアイコンメニューから両方のアクションを確認します。

索引モデルが issue の本文から書いたものです。