Promise Tracker | English and French language support (v2)

[RalphOwah]

English and French language support (v2)

What: The old site offered a language switcher (En, Fr, Am, Arabic) routed by path. On v2 these routes go to 404 page, and there is no switcher.

Expected:

• A user can switch between English and French from the header. The URL reflects the language, English at root and French under /fr.
• Both the interface and the promise content itself (title, description, evidence) display in the chosen language, not just the menus and labels.
• Anything untranslated falls back to English rather than showing blank or a raw key. Links stay shareable and bookmarkable per language.
• Scope for v2: English (default) and French only.
• Locale routing by path prefix. English at root, French under /fr, standard Next.js i18n.
• UI strings come from translation files per locale, not hardcoded.
• The switcher preserves the current page when changing language, it does not reset to home.
  Missing translations fall back to English.
• Layer 1, UI chrome (menu, buttons, Filter By, Sort By, Search). Bounded, developer owned, translate once.
• Layer 2, Payload labels (category names, status names, section headings). Bounded, needs a one-time French translation pass stored per locale in Payload.
• Layer 3, promise content (title, description, evidence). This must translate too. Unbounded and ongoing since it grows with every promise.

[kelvinkipruto]

@RalphOwah I presume this is for V2, and we shouldn't implement it yet.