The per-app language picker in iOS Settings only appears when the built app
declares multiple localizations. Add the planned languages to the Xcode
project's knownRegions (so Xcode compiles their .lproj from the String
Catalog), and have `generate` keep CFBundleLocalizations in Info.plist in sync
with supportedLanguages (currently en, fr).
Add localization/ — one strings.json is the source of truth for every
user-facing string, and a Bun CLI generates the platform files:
loc migrate rebuild strings.json from existing platform files (one-time)
loc validate structural checks (plural `other`, arg refs, coverage)
loc generate emit .xcstrings (Apple) + per-language strings.xml (KMP)
Canonical `{name}` placeholders are converted to each platform's positional
printf tokens using declared arg types. Plurals use CLDR categories and emit
native forms: xcstrings plural variations and Compose <plurals> blocks.
Migration folds the KMP `transfer_file_count_one`/`_other` pair into a single
plural key, so `transferFileCountResource` now returns the plural resource and
callers resolve it with pluralStringResource.
