feat: i18n on Filament admin sidebar — 54 resources/pages translated

User screenshots showed the tenant admin panel (Filament) had sidebar
labels stuck in Romanian even when switching to Russian: 'Cereri',
'Calendar vizual', 'Atelierul meu', 'KPI mecanici', 'Fișe lucru',
'Norme-ore', 'Tehnicieni', 'Șabloane servicii', 'Depozite', 'Scaner',
'Depozit', 'VIN-căutare', 'Furnizori', 'Achiziții', 'Procentaj',
'Coeficienți preț', plus all group headers.

Root cause: every Filament Resource and Page had static properties
'protected static ?string $navigationLabel = "Fișe lucru"' — string
literals baked into class definitions. Static properties don't run
through the translation layer.

Fix in two parts:

1. New translation files with 52 label keys + 12 group keys:
   - lang/ro/nav.php — Romanian (identity)
   - lang/ru/nav.php — full Russian translations (Заказ-наряды,
     Автомобили, Клиенты, Календарь, Моя мастерская, Механики KPI,
     Настройки, etc.)
   - lang/en/nav.php — English translations (Work orders, Vehicles,
     Clients, Calendar, My workshop, Mechanic KPI, Settings, etc.)

   Keyed by the Romanian original so lookups map 1:1 —
   'nav.label.Fișe lucru' returns 'Заказ-наряды' in RU, 'Work orders'
   in EN, 'Fișe lucru' in RO.

2. Python transformer converted 54 files:
   - 33 Filament Tenant Resources
   - 15 Filament Tenant Pages
   - 4 Filament Central Resources
   - 1 Filament Central Page
   - 1 Widget

   Each 'protected static ?string $navigationLabel = "X";' became
   'public static function getNavigationLabel(): string { return
   __("nav.label.X"); }'. Same treatment for $navigationGroup.

Cleanup: 6 resources already had manually-added getNavigationLabel
methods from an earlier partial effort — those used flat JSON keys
(__("Cereri")) that never resolved. Deduped so only the nav.label.*
version remains.

Untouched (intentional):
- $modelLabel / $pluralModelLabel (used in breadcrumbs and headings —
  still hardcoded, next tier of work)
- Section titles, column headers, form field labels (medium priority)
- $navigationSort (numeric, no translation needed)
- $navigationIcon (icon reference)

Suite: 306 passed (853 assertions). Unchanged.

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

lang/en/nav.php

@@ -0,0 +1,74 @@
+<?php
+
+return [
+    'group' => [
+        'Admin' => 'Admin',
+        'Analiză' => 'Analytics',
+        'Anvelope' => 'Tires',
+        'CRM' => 'CRM',
+        'Depozit' => 'Warehouse',
+        'Finanțe' => 'Finance',
+        'Magazin' => 'Shop',
+        'Marketing' => 'Marketing',
+        'Service' => 'Service',
+        'Stoc & Finanțe' => 'Stock & Finance',
+        'Subcontractare' => 'Subcontracting',
+        'Tinichigerie' => 'Bodyshop',
+    ],
+
+    'label' => [
+        'API Tokens' => 'API Tokens',
+        'Achiziții' => 'Purchases',
+        'Angajați' => 'Employees',
+        'Apeluri' => 'Calls',
+        'Asistent AI' => 'AI Assistant',
+        'Atelierul meu' => 'My workshop',
+        'Automobile' => 'Vehicles',
+        'Backup' => 'Backup',
+        'Bonusuri & avansuri' => 'Bonuses & advances',
+        'Calendar' => 'Calendar',
+        'Calendar vizual' => 'Visual calendar',
+        'Canale marketing' => 'Marketing channels',
+        'Cereri' => 'Leads',
+        'Cheltuieli' => 'Expenses',
+        'Clienți' => 'Clients',
+        'Clienți magazin' => 'Shop customers',
+        'Coeficienți preț' => 'Price coefficients',
+        'Comenzi online' => 'Online orders',
+        'Companii' => 'Companies',
+        'Depozit' => 'Warehouse',
+        'Depozite' => 'Warehouses',
+        'Facturi & abonamente' => 'Invoices & subscriptions',
+        'Finanțe (consolidat)' => 'Finance (consolidated)',
+        'Fișe lucru' => 'Work orders',
+        'Furnizori' => 'Suppliers',
+        'Import factură Excel' => 'Excel invoice import',
+        'Integrări' => 'Integrations',
+        'Jurnal activitate' => 'Activity log',
+        'KPI mecanici' => 'Mechanic KPI',
+        'Lucrări terți' => 'Subcontractor jobs',
+        'Norme-ore' => 'Labor catalog',
+        'Pipeline' => 'Pipeline',
+        'Pipeline (tabel)' => 'Pipeline (table)',
+        'Planuri' => 'Plans',
+        'Plăți' => 'Payments',
+        'Posturi de lucru' => 'Work bays',
+        'Procentaj' => 'Commission',
+        'Rapoarte' => 'Reports',
+        'Recomandări' => 'Recommendations',
+        'Roluri & Drepturi' => 'Roles & permissions',
+        'Salarii' => 'Salaries',
+        'Scaner' => 'Scanner',
+        'Seturi anvelope' => 'Tire sets',
+        'Setări' => 'Settings',
+        'Setări plăți' => 'Payment settings',
+        'Subcontractori' => 'Subcontractors',
+        'Tehnicieni' => 'Technicians',
+        'Template-uri mesaje' => 'Message templates',
+        'Tinichigerie / Detailing' => 'Bodyshop / Detailing',
+        'Utilizatori' => 'Users',
+        'VIN-căutare' => 'VIN search',
+        'Încărcare STO' => 'Workshop load',
+        'Șabloane servicii' => 'Service templates',
+    ],
+];