Add internationalization (i18n) support

[akonan]

Description

Support for multi-language wireframes and RTL (right-to-left) layouts.

Features

• RTL layout support (for Arabic, Hebrew, etc.)
• Language hints in markdown: {:lang=ar :dir=rtl}
• Localized component labels
• Multiple language examples in docs

Example

{:lang=ar :dir=rtl}
## نموذج اتصال
[إرسال]

Priority

Low

Labels

enhancement, i18n, internationalization