Remove approximate processing times from remove-bg quality options.
Update tool count from 37 to 33 across README, settings dialog, login
page, and i18n strings to reflect the accurate count.
Create translation key system in packages/shared/src/i18n/ with full
English locale covering common actions, all 37 tools, settings sections,
auth, pipeline, and navigation strings. Add useI18n hook that returns
typed translations. Architecture enables adding new languages by
creating locale files matching the TranslationKeys type.