Replace numerous hardcoded English strings with I18n lookups (t / I18n.t) across controllers, views, helpers, and components, and convert model validation error messages to symbol keys. Added multiple locale files under config/locales for models and views. This centralizes user-facing notices/alerts, UI text, import/validation messages, and prepares the app for localization and easier translation maintenance.
Extend privacy mode coverage to remaining financial views
Transfers, trades, valuations, and holdings detail views were missing
the privacy-sensitive class, leaving amounts visible when privacy mode
was enabled. Also adds blur to the summary card partial (used by credit
cards, loans, etc.), account chart balances, and time series chart
containers (dashboard net worth and per-account charts).
