refactor(deployment): Remove WireGuard VPN dependency and restore public service access

Remove WireGuard integration from production deployment to simplify infrastructure:
- Remove docker-compose-direct-access.yml (VPN-bound services)
- Remove VPN-only middlewares from Grafana, Prometheus, Portainer
- Remove WireGuard middleware definitions from Traefik
- Remove WireGuard IPs (10.8.0.0/24) from Traefik forwarded headers

All monitoring services now publicly accessible via subdomains:
- grafana.michaelschiemer.de (with Grafana native auth)
- prometheus.michaelschiemer.de (with Basic Auth)
- portainer.michaelschiemer.de (with Portainer native auth)

All services use Let's Encrypt SSL certificates via Traefik.

tests/debug/generate-comparison-qrcode.php

@@ -0,0 +1,78 @@
+<?php
+
+declare(strict_types=1);
+
+require_once __DIR__ . '/../../vendor/autoload.php';
+
+use App\Framework\QrCode\QrCodeGenerator;
+use App\Framework\QrCode\QrCodeRenderer;
+use App\Framework\QrCode\ValueObjects\ErrorCorrectionLevel;
+use App\Framework\QrCode\ValueObjects\QrCodeConfig;
+use App\Framework\QrCode\ValueObjects\QrCodeVersion;
+use App\Framework\QrCode\ValueObjects\EncodingMode;
+use App\Framework\QrCode\ValueObjects\QrCodeStyle;
+
+echo "=== Generate Comparison QR Code ===\n\n";
+
+// Generate with exact same parameters as problematic SVG
+// SVG shows: 580x580 canvas, 20px modules, 80px quiet zone (4 modules)
+$config = new QrCodeConfig(
+    version: QrCodeVersion::fromNumber(1),
+    errorCorrectionLevel: ErrorCorrectionLevel::M,
+    encodingMode: EncodingMode::BYTE
+);
+
+// Try different test data
+$testDataSets = [
+    'HELLO WORLD',
+    'HELLO',
+    'A',
+    '12345',
+    'https://example.com',
+];
+
+foreach ($testDataSets as $testData) {
+    echo "=== Testing with: '{$testData}' ===\n";
+    
+    try {
+        $matrix = QrCodeGenerator::generate($testData, $config);
+        
+        // Render with matching parameters
+        $style = QrCodeStyle::large(); // 20px modules, 4 module quiet zone
+        $renderer = new QrCodeRenderer();
+        $svg = $renderer->renderCustom($matrix, $style, false);
+        
+        // Save
+        $filename = preg_replace('/[^a-zA-Z0-9]/', '_', $testData);
+        $filepath = __DIR__ . "/test-qrcodes/test-{$filename}.svg";
+        file_put_contents($filepath, $svg);
+        
+        echo "✅ Generated: {$filepath}\n";
+        echo "   Matrix size: {$matrix->getSize()}x{$matrix->getSize()}\n";
+        
+        // Check canvas size
+        if (preg_match('/width="(\d+)" height="(\d+)"/', $svg, $matches)) {
+            echo "   Canvas size: {$matches[1]}x{$matches[2]}\n";
+            if ((int)$matches[1] === 580) {
+                echo "   ✅ Canvas size matches problematic SVG\n";
+            }
+        }
+        
+        echo "\n";
+        
+    } catch (\Exception $e) {
+        echo "❌ Error: " . $e->getMessage() . "\n\n";
+    }
+}
+
+echo "=== Summary ===\n";
+echo "All test QR codes generated with:\n";
+echo "  - Canvas: 580x580px\n";
+echo "  - Module size: 20px\n";
+echo "  - Quiet zone: 80px (4 modules)\n";
+echo "\n";
+echo "Try scanning these QR codes to see if any work.\n";
+echo "If they all work, the issue is with the data in the problematic SVG.\n";
+echo "If none work, there might be a systematic issue.\n";
+
+