Add browser-accessible smoke test at /tools/smoke-test

- Visit /tools/smoke-test in browser to get full HTML report
- Dark UI with stats cards, error details, and "Copy for Claude" button
- Requires settings.edit permission (admin only)
- Still works via CLI: php tools/smoke_test.php [url] [email] [pass]
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Modules/Settings/Controllers/SmokeTestController.php

+<?php
+declare(strict_types=1);
+
+namespace App\Modules\Settings\Controllers;
+
+use App\Core\Controller;
+use App\Core\Request;
+use App\Core\Response;
+
+class SmokeTestController extends Controller
+{
+    public function run(Request $request): Response
+    {
+        $this->authorize('settings.edit');
+
+        ob_start();
+        require __DIR__ . '/../../../../tools/smoke_test.php';
+        $html = ob_get_clean();
+
+        return (new Response())->html($html);
+    }
+}

app/Modules/Settings/Routes.php

@@ -11,4 +11,7 @@ return [
     ['POST', '/settings/branding/logo',         'Settings\Controllers\BrandingController@updateLogo',         ['auth', 'csrf'], 'settings.edit'],
     ['POST', '/settings/branding/carnet',       'Settings\Controllers\BrandingController@updateCarnetDesign', ['auth', 'csrf'], 'settings.edit'],
     ['POST', '/settings/branding/receipt',      'Settings\Controllers\BrandingController@updateReceiptDesign',['auth', 'csrf'], 'settings.edit'],
+
+    // Smoke Test Tool
+    ['GET',  '/tools/smoke-test',              'Settings\Controllers\SmokeTestController@run',  ['auth'], 'settings.edit'],
 ];
\ No newline at end of file