Add configurable system settings service

app/Services/System/SystemSettingService.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace App\Services\System;
+
+use Illuminate\Support\Arr;
+
+class SystemSettingService
+{
+    /**
+     * Ambil semua konfigurasi sistem dengan struktur terkelompok.
+     */
+    public function all(): array
+    {
+        return config('system', []);
+    }
+
+    /**
+     * Ambil satu nilai konfigurasi dengan dukungan dot notation.
+     */
+    public function get(string $key, mixed $default = null): mixed
+    {
+        return Arr::get($this->all(), $key, $default);
+    }
+
+    /**
+     * Set konfigurasi secara runtime tanpa menyentuh database.
+     */
+    public function set(string $key, mixed $value): void
+    {
+        $settings = $this->all();
+        Arr::set($settings, $key, $value);
+
+        config(['system' => $settings]);
+    }
+}