fix: PSR-4 compliance — rename core/middleware/services to PascalCase for Linux server compatibility

app/Core/Security.php

@@ -0,0 +1,42 @@
+<?php
+/**
+ * Simple Security Helpers
+ */
+
+declare(strict_types=1);
+
+namespace App\Core;
+
+final class Security
+{
+    /**
+     * Recursively sanitize input data (strings and arrays)
+     */
+    public static function sanitize($data)
+    {
+        if (is_array($data)) {
+            foreach ($data as $key => $value) {
+                $data[$key] = self::sanitize($value);
+            }
+        } else if (is_string($data)) {
+            $data = htmlspecialchars(strip_tags(trim($data)), ENT_QUOTES, 'UTF-8');
+        }
+        return $data;
+    }
+
+    public static function generateRandomString(int $length = 64): string
+    {
+        return bin2hex(random_bytes($length / 2));
+    }
+
+    public static function sign(string $data, string $secret): string
+    {
+        return hash_hmac('sha256', $data, $secret);
+    }
+
+    public static function verifySignature(string $data, string $signature, string $secret): bool
+    {
+        $expected = self::sign($data, $secret);
+        return hash_equals($expected, $signature);
+    }
+}