Deploy 1: i18n + Notifications + Global Search + Tests

- SetLocale middleware (ro/ru/en, session-first, user-persisted)
- Lang switcher in topbar (Filament render hook USER_MENU_BEFORE)
- POST /locale/{lang} route persists to user.locale + session
- Database notifications enabled on tenant panel (30s polling)
- GlobalSearch (Cmd+K / Ctrl+K) on Client, Vehicle, WorkOrder, Lead, Part
- Tests: TenantIsolation (4), AuthFlow (2), WorkOrderCalc (3), MarkupRule (3)

app/Http/Middleware/SetLocale.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace App\Http\Middleware;
+
+use App\Tenancy\TenantManager;
+use Closure;
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\App;
+use Illuminate\Support\Facades\Auth;
+use Carbon\Carbon;
+
+class SetLocale
+{
+    private const SUPPORTED = ['ro', 'ru', 'en'];
+
+    public function handle(Request $request, Closure $next)
+    {
+        $locale = $this->resolve($request);
+
+        App::setLocale($locale);
+        Carbon::setLocale($locale);
+
+        return $next($request);
+    }
+
+    private function resolve(Request $request): string
+    {
+        $session = $request->session()->get('locale');
+        if ($session && in_array($session, self::SUPPORTED, true)) {
+            return $session;
+        }
+
+        $user = Auth::user();
+        if ($user && ! empty($user->locale) && in_array($user->locale, self::SUPPORTED, true)) {
+            return $user->locale;
+        }
+
+        $tenant = app(TenantManager::class)->current();
+        $tenantLang = $tenant?->settings['language'] ?? null;
+        if ($tenantLang && in_array($tenantLang, self::SUPPORTED, true)) {
+            return $tenantLang;
+        }
+
+        return config('app.locale', 'ro');
+    }
+}