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/PartResource/RelationManagers/PriceHistoryRelationManager.php

@@ -10,26 +10,31 @@ class PriceHistoryRelationManager extends RelationManager
 {
     protected static string $relationship = 'priceHistory';
 
-    protected static ?string $title = 'Istoric prețuri furnizori';
+    protected static ?string $title = null;
+
+    public static function getTitle(\Illuminate\Database\Eloquent\Model $ownerRecord, string $pageClass): string
+    {
+        return __('Istoric prețuri furnizori');
+    }
 
     public function table(Table $table): Table
     {
         return $table
             ->columns([
                 Tables\Columns\TextColumn::make('observed_at')
-                    ->label('Data')
+                    ->label(__('Data'))
                     ->dateTime('d.m.Y H:i')
                     ->sortable(),
-                Tables\Columns\TextColumn::make('supplier.name')->label('Furnizor')->searchable(),
-                Tables\Columns\TextColumn::make('purchase.number')->label('PO')->placeholder('—'),
+                Tables\Columns\TextColumn::make('supplier.name')->label(__('Furnizor'))->searchable(),
+                Tables\Columns\TextColumn::make('purchase.number')->label(__('PO'))->placeholder('—'),
                 Tables\Columns\TextColumn::make('price')
                     ->money('MDL')
                     ->alignRight()
                     ->sortable(),
-                Tables\Columns\TextColumn::make('currency')->label('Val.'),
+                Tables\Columns\TextColumn::make('currency')->label(__('Val.')),
             ])
             ->defaultSort('observed_at', 'desc')
-            ->emptyStateHeading('Niciun preț înregistrat')
-            ->emptyStateDescription('Prețurile se înregistrează automat la fiecare recepție de PO.');
+            ->emptyStateHeading(__('Niciun preț înregistrat'))
+            ->emptyStateDescription(__('Prețurile se înregistrează automat la fiecare recepție de PO.'));
     }
 }