Add Persian (Farsi) translation with fa-IR locale (keep existing RTL support)

[persinsmart]

Is your feature request related to a problem? Please describe

The app already has excellent RTL layout and bidirectional text support when Arabic (ar) is selected — Persian text displays correctly right-to-left.

The only issue is that the entire user interface (menus, buttons, dialogs, settings, error messages, etc.) remains in Arabic.
More than 110 million Persian/Farsi speakers in Iran, Afghanistan (Dari), and Tajikistan are forced to use the app in Arabic, which is not their native language and creates confusion.

Describe the solution you'd like

• Add a new separate Persian locale: fa or fa-IR
• Provide complete Farsi translations for all UI strings
• Automatically use the existing RTL styling and BiDi handling when Persian is selected (no need to re-implement RTL)

Additional context

Persian and Arabic share the same script and direction, so RTL support is already solved. We only need the translation layer.
Many of us in the Persian community are ready to contribute translations and review them quickly.

Thank you! 🇮🇷