Add Persian (Farsi) language support #30000

Is your proposal related to a problem?

Persian/Farsi (fa) users currently do not have a complete localized experience in Cal.com.

Although RTL infrastructure is being discussed for languages such as Arabic and Hebrew, Persian users also need proper RTL support, Persian translations, and calendar support for a better booking experience.

Without Persian localization, users in Persian-speaking communities face issues such as incorrect text direction, unfamiliar UI language, and lack of support for the Persian (Jalali) calendar.

Describe the solution you'd like

I would like to add full Persian/Farsi (fa) language support, including:

• Complete Persian UI translation
• RTL layout support for Persian pages
• Proper Persian typography (for example Vazirmatn font)
• Persian date/calendar support (Jalali calendar)
• Correct formatting for dates, times, and booking flows
• RTL testing for booking pages and embedded components

I would be happy to help implement and test this feature.

Describe alternatives you've considered

Currently, Persian-speaking users can use the English interface or manually customize/fork the project, but this does not provide a native localized experience.

Supporting Persian as an official locale would make Cal.com more accessible for Persian-speaking users.

Additional context

Persian (fa) is already commonly considered an RTL language alongside Arabic and Hebrew. Adding Persian support would extend the existing RTL efforts and improve accessibility for another large user community.

Related RTL discussion:
#21889

I can contribute with:

• Persian translations
• RTL testing
• Localization improvements
• Persian calendar integration

Requirement/Document

Possible references:

• Unicode CLDR Persian locale data:
  https://cldr.unicode.org/

• Persian calendar (Jalali) support documentation:
  https://github.com/iamkun/dayjs/tree/dev/src/plugin/jalali