Add gold credit feature gated by SuperAdmin enable_gold_credit.

Port tables, APIs, and overdue cron from goldali, default the flag off, and keep customer routes behind auth.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/Console/Commands/ProcessGoldCreditOverdue.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace App\Console\Commands;
+
+use App\Services\GoldCreditService;
+use Illuminate\Console\Command;
+
+class ProcessGoldCreditOverdue extends Command
+{
+    protected $signature = 'gold-credit:process-overdue';
+
+    protected $description = 'SMS هشدار سررسید اقساط اعتبار طلایی و اعمال جریمه روزانه پس از مهلت';
+
+    public function handle(GoldCreditService $service): int
+    {
+        $result = $service->processOverdueInstallments();
+        $this->info(sprintf(
+            'warnings=%d penalties=%d reminders=%d',
+            $result['warnings'] ?? 0,
+            $result['penalties'] ?? 0,
+            $result['reminders'] ?? 0
+        ));
+
+        return self::SUCCESS;
+    }
+}

app/Console/Kernel.php

@@ -13,6 +13,11 @@ class Kernel extends ConsoleKernel
 
     protected function schedule(Schedule $schedule)
     {
+        $schedule->command('gold-credit:process-overdue')
+            ->everyFiveMinutes()
+            ->name('gold_credit_process_overdue')
+            ->withoutOverlapping();
+
         // تیک قیمت — ۶ بار در دقیقه با فاصله ۱۰ ثانیه (montzar + zaarbox + محصولات)
         // نیاز: * * * * * php artisan schedule:run
         // یا یک‌بار: php artisan schedule:bootstrap