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/analyze-expected-codewords.php

@@ -0,0 +1,106 @@
+<?php
+
+declare(strict_types=1);
+
+echo "=== Analyzing Expected Codewords ===\n\n";
+
+$expectedCodewords = [64, 180, 132, 84, 196, 196, 242, 5, 116, 245, 174, 59, 64, 109, 236, 233];
+
+// Convert to bits
+$expectedBits = '';
+foreach ($expectedCodewords as $cw) {
+    $expectedBits .= str_pad(decbin($cw), 8, '0', STR_PAD_LEFT);
+}
+
+echo "Expected bit string (128 bits):\n";
+echo $expectedBits . "\n\n";
+
+// Decode expected
+echo "=== Decoding Expected Codewords ===\n";
+
+// Mode (4 bits)
+$modeBits = substr($expectedBits, 0, 4);
+$mode = bindec($modeBits);
+echo "Mode (bits 0-3): {$modeBits} = {$mode} (expected: 4 for byte mode)\n";
+
+// Count (8 bits)
+$countBits = substr($expectedBits, 4, 8);
+$count = bindec($countBits);
+echo "Count (bits 4-11): {$countBits} = {$count}\n";
+
+// Data (11 bytes = 88 bits)
+echo "\nData bytes (bits 12-99):\n";
+$decodedData = '';
+for ($i = 0; $i < $count; $i++) {
+    $byteStart = 12 + ($i * 8);
+    $byteBits = substr($expectedBits, $byteStart, 8);
+    $byte = bindec($byteBits);
+    $decodedData .= chr($byte);
+    echo "  Byte {$i}: {$byteBits} = {$byte} = '{$decodedData[$i]}'\n";
+}
+
+echo "\nDecoded data: '{$decodedData}'\n";
+echo "Expected: 'HELLO WORLD'\n";
+
+if ($decodedData === 'HELLO WORLD') {
+    echo "✅ Expected codewords decode to 'HELLO WORLD'!\n\n";
+} else {
+    echo "❌ Expected codewords don't decode correctly!\n\n";
+}
+
+// Now check what comes after data (bits 100-127)
+echo "Bits after data (100-127):\n";
+$afterData = substr($expectedBits, 100);
+echo $afterData . "\n\n";
+
+// Convert to codewords
+$afterDataCodewords = [];
+for ($i = 0; $i < strlen($afterData); $i += 8) {
+    $byte = substr($afterData, $i, 8);
+    $afterDataCodewords[] = bindec($byte);
+}
+
+echo "Codewords 12-15: " . implode(', ', $afterDataCodewords) . "\n";
+echo "Expected: 64, 109, 236, 233\n";
+
+// Our encoding
+echo "\n=== Our Encoding (for comparison) ===\n";
+$ourBits = "0100" . // Mode
+           "00001011" . // Count
+           "0100100001000101010011000100110001001111001000000101011101001111010100100100110001000100" . // Data (88 bits)
+           "0000" . // Terminator
+           "11101100" . // Pad 1
+           "00010001" . // Pad 2
+           "11101100"; // Pad 3
+
+echo "Our bit string (128 bits):\n";
+echo $ourBits . "\n\n";
+
+// Compare
+echo "=== Comparison ===\n";
+$differences = [];
+for ($i = 0; $i < 128; $i++) {
+    if ($ourBits[$i] !== $expectedBits[$i]) {
+        $differences[] = $i;
+    }
+}
+
+echo "Differences: " . count($differences) . "\n";
+echo "Positions: " . implode(', ', array_slice($differences, 0, 30)) . "\n\n";
+
+// Check if our data bits match
+$ourDataBits = substr($ourBits, 12, 88);
+$expectedDataBits = substr($expectedBits, 12, 88);
+if ($ourDataBits === $expectedDataBits) {
+    echo "✅ Data bits match!\n";
+} else {
+    echo "❌ Data bits differ!\n";
+    for ($i = 0; $i < 88; $i++) {
+        if ($ourDataBits[$i] !== $expectedDataBits[$i]) {
+            echo "Data bit {$i} differs: got '{$ourDataBits[$i]}', expected '{$expectedDataBits[$i]}'\n";
+            break;
+        }
+    }
+}
+
+