i18n: fix widget heading, translate Select options from model consts, +40 keys

- LowStockTable: rename getHeading → getTableHeading (correct Filament API)
- Global I18n::opts() helper wraps Model::CONST values in __() so
  Select dropdowns show translated status/type/season/etc. labels
- Sed-transform ->options(X::CONST), ->options(array_combine(X::A,X::A)),
  and formatStateUsing(fn($s)=>X::CONST[$s]??$s) → wrap with __()
  (58 options + 10 combines + 7 formatStateUsing across 28 files)
- CalendarBoard: all 7 day names now via __() (was missing 4)
- calendar-board.blade: fix untranslated 'săptămâna curentă', 'capacitate',
  'rata confirmare', 'mediu', 'plin', 'Pod / Zi' / 'Mecanic / Zi'
- +40 RU/EN translations (Client & Auto, Maistru / Mecanic, Programat,
  Sosit, Finalizat, Anulat, Neprezentat, days of week, calendar KPIs)

All 306 tests pass.

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

app/Filament/Tenant/Resources/PricingCoefficientResource.php

@@ -57,7 +57,7 @@ class PricingCoefficientResource extends Resource
                 ->schema([
                     Forms\Components\CheckboxList::make('conditions.classes')
                         ->label(__('Clase auto'))
-                        ->options(PricingCoefficient::VEHICLE_CLASSES)
+                        ->options(\App\Support\I18n::opts(PricingCoefficient::VEHICLE_CLASSES))
                         ->columns(2)
                         ->columnSpanFull(),
                     Forms\Components\CheckboxList::make('conditions.body_types')
@@ -75,7 +75,7 @@ class PricingCoefficientResource extends Resource
                     Forms\Components\Toggle::make('conditions.client_vip')->label(__('Doar clienți VIP')),
                     Forms\Components\CheckboxList::make('conditions.urgency')
                         ->label(__('Urgență'))
-                        ->options(PricingCoefficient::URGENCY)
+                        ->options(\App\Support\I18n::opts(PricingCoefficient::URGENCY))
                         ->columns(3)
                         ->columnSpanFull(),
                 ]),