feat(i18n): fix widgets, pipeline & mechanic boards + missing translations

Follow-up to previous i18n pass — user reported many visible RO strings on
EN/RU locales because auto-wrap missed:
  - Stat::make() first-arg labels in StatsOverview, FinanceOverview, PlatformStats
  - $heading static in LowStockTable (converted to getHeading() method)
  - Pipeline board Blade view: 40+ literal strings wrapped with {{ __() }}
  - Mechanic board Blade view: statuses, buttons, block modal
  - PipelineBoard.php hardcoded tag labels, stage labels, notify strings
  - MechanicBoard.php confirmBlock notification

Added human RU + EN translations for the visible strings shown in the
screenshots (dashboard widgets, Client/Vehicle list breadcrumbs & columns,
pipeline board topbar/stats/filters/cards/detail panel/quick actions,
mechanic board stats/statuses/block modal). All 306 tests pass.

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

app/Filament/Tenant/Widgets/LowStockTable.php

@@ -13,7 +13,12 @@ class LowStockTable extends BaseWidget
 
     protected int|string|array $columnSpan = 'full';
 
-    protected static ?string $heading = '⚠️ Stoc minim atins';
+    protected static ?string $heading = null;
+
+    public function getHeading(): string
+    {
+        return '⚠️ ' . __('Stoc minim atins');
+    }
 
     public function table(Table $table): Table
     {