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/ServiceTemplateResource/RelationManagers/ItemsRelationManager.php

@@ -30,7 +30,7 @@ class ItemsRelationManager extends RelationManager
         return $schema->components([
             Forms\Components\Select::make('kind')
                 ->label(__('Tip'))
-                ->options(ServiceTemplateItem::KINDS)
+                ->options(\App\Support\I18n::opts(ServiceTemplateItem::KINDS))
                 ->default('labor')
                 ->live()
                 ->required(),