Replace all hardcoded Russian strings in ScanScreen and _LoadingDialog
with AppLocalizations keys; add addFromReceiptOrPhoto, chooseMethod,
photoReceipt, photoReceiptSubtitle, photoProducts, photoProductsSubtitle,
recognizing keys to all 12 ARB files and regenerate AppLocalizations.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Add flutter_localizations + intl, 12 ARB files (en/ru/es/de/fr/it/pt/zh/ja/ko/ar/hi),
replace all hardcoded Russian UI strings with AppLocalizations, detect system locale
on first launch, localise bottom nav bar labels, document rule in CLAUDE.md.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>