Follow System Locale with Optional Override

Describe your improvement idea or feature request

Allow the Taskwarrior Flutter app to automatically follow the device system language by default, with an optional toggle in Settings to manually override the language.

Problem

Currently, the app does not automatically follow the device's system locale.

Most modern mobile applications:

• Use the system language by default
• Allow users to manually override it in settings

Without this behavior:

• The app may not feel native
• International users may experience friction
• Localization support is limited in usability

How would you like to see it implemented?

Proposed Solution

1. Follow System Locale by Default

If no language is manually selected:

• The app should use the device Locale
• If the locale is unsupported, fallback to English

Example:

• Device language: pa (Punjabi) → App uses Punjabi (if supported)
• Unsupported language → Fallback to English

---

2. Add “Follow System Language” Toggle

In Settings:

Put here any screenshots or videos (optional)

No response

How can we contact you (optional)

No response

Would you like to work on this issue?

Yes

By submitting this issue, I have confirmed that:

• I have starred the repo ⭐ and watched 👀 it on GitHub and followed the contribution guidelines.

首先跟踪应用当前的本地化入口点和 Settings 屏幕，然后检查支持的 locale 以及设备 Locale 的处理方式。完成标准是：应用默认遵循系统语言，在不支持时回退到英语，并允许用户从 Settings 覆盖这一选择。