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/AppointmentResource.php

@@ -66,7 +66,7 @@ class AppointmentResource extends Resource
                         ->options(fn () => User::pluck('name', 'id'))
                         ->searchable(),
                     Forms\Components\Select::make('status')
-                        ->options(Appointment::STATUSES)
+                        ->options(\App\Support\I18n::opts(Appointment::STATUSES))
                         ->default('scheduled')
                         ->required(),
                 ]),
@@ -103,7 +103,7 @@ class AppointmentResource extends Resource
                 Tables\Columns\TextColumn::make('vehicle.plate')->label(__('Auto'))->placeholder('—'),
                 Tables\Columns\TextColumn::make('master.name')->label(__('Maistru'))->placeholder('—'),
                 Tables\Columns\TextColumn::make('status')
-                    ->formatStateUsing(fn ($state) => Appointment::STATUSES[$state] ?? $state)
+                    ->formatStateUsing(fn ($state) => __(Appointment::STATUSES[$state] ?? $state))
                     ->badge()
                     ->colors([
                         'gray' => ['scheduled'],
@@ -119,7 +119,7 @@ class AppointmentResource extends Resource
                 Tables\Filters\Filter::make('upcoming')
                     ->label(__('Viitoare'))
                     ->query(fn ($q) => $q->where('date', '>=', today())),
-                Tables\Filters\SelectFilter::make('status')->options(Appointment::STATUSES),
+                Tables\Filters\SelectFilter::make('status')->options(\App\Support\I18n::opts(Appointment::STATUSES)),
                 Tables\Filters\SelectFilter::make('post_id')
                     ->label(__('Pod'))
                     ->options(fn () => Post::pluck('name', 'id')),