feat(i18n): wrap 1103 hardcoded UI strings across Filament with __()

- Convert static $modelLabel/$pluralModelLabel/$title to getter methods
- Wrap ->label()/->placeholder()/->helperText()/->description()/->title()/->body() args
- Wrap Section::make()/Fieldset::make()/Notification::make()->title() args
- Fix RelationManagers::getTitle() signature to match parent (Model, string)
- Fix Pages::getTitle() to instance method (BasePage::getTitle is non-static)
- Extend lang/ru.json + lang/en.json with 700+ common terms; identity fallback for the rest
- Remove duplicate getters in 5 resources that had manual getModelLabel already

All 306 tests pass. Missing translations fall back to the RO key so the UI never breaks.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/Filament/Tenant/Resources/VehicleResource/Pages/ListVehicles.php

@@ -17,16 +17,16 @@ class ListVehicles extends ListRecords
     {
         return [
             Actions\Action::make('export')
-                ->label('Export CSV')
+                ->label(__('Export CSV'))
                 ->icon('heroicon-m-arrow-down-tray')
                 ->color('gray')
                 ->action(fn () => app(CsvImportExport::class)->exportVehicles()),
             Actions\Action::make('import')
-                ->label('Import CSV')
+                ->label(__('Import CSV'))
                 ->icon('heroicon-m-arrow-up-tray')
                 ->color('gray')
-                ->modalHeading('Import mașini din CSV')
-                ->modalDescription('CSV cu header: ' . implode(', ', CsvImportExport::VEHICLE_COLUMNS) . '. Coloana client_phone trebuie să existe deja la clienți.')
+                ->modalHeading(__('Import mașini din CSV'))
+                ->modalDescription(__('CSV cu header: ' . implode(', ', CsvImportExport::VEHICLE_COLUMNS) . '. Coloana client_phone trebuie să existe deja la clienți.'))
                 ->schema([
                     Forms\Components\FileUpload::make('file')
                         ->required()