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/Widgets/LowStockTable.php

@@ -25,13 +25,13 @@ class LowStockTable extends BaseWidget
                     ->orderBy('qty')
             )
             ->columns([
-                Tables\Columns\TextColumn::make('name')->label('Piesă')->wrap()->searchable(),
-                Tables\Columns\TextColumn::make('article')->label('Cod')->placeholder('—'),
-                Tables\Columns\TextColumn::make('qty')->label('Stoc')->alignRight()
+                Tables\Columns\TextColumn::make('name')->label(__('Piesă'))->wrap()->searchable(),
+                Tables\Columns\TextColumn::make('article')->label(__('Cod'))->placeholder('—'),
+                Tables\Columns\TextColumn::make('qty')->label(__('Stoc'))->alignRight()
                     ->color(fn ($state) => $state <= 0 ? 'danger' : 'warning')
                     ->weight('bold'),
-                Tables\Columns\TextColumn::make('min_qty')->label('Min.')->alignRight(),
-                Tables\Columns\TextColumn::make('preferredSupplier.name')->label('Furnizor')->placeholder('—'),
+                Tables\Columns\TextColumn::make('min_qty')->label(__('Min.'))->alignRight(),
+                Tables\Columns\TextColumn::make('preferredSupplier.name')->label(__('Furnizor'))->placeholder('—'),
             ])
             ->paginated(false)
             ->defaultSort('qty');