Add optional owner gateway routing to Merchant.

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

app/Models/PaymentGatewaySetting.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+class PaymentGatewaySetting extends Model
+{
+    public const PROVIDER_PAYSTACK = 'paystack';
+
+    protected $fillable = ['owner_ref', 'provider', 'public_key', 'secret_key', 'is_active', 'metadata'];
+
+    protected function casts(): array
+    {
+        return [
+            'public_key' => 'encrypted',
+            'secret_key' => 'encrypted',
+            'is_active' => 'boolean',
+            'metadata' => 'array',
+        ];
+    }
+
+    public function isConfigured(): bool
+    {
+        return $this->is_active
+            && $this->provider === self::PROVIDER_PAYSTACK
+            && str_starts_with(trim((string) $this->public_key), 'pk_')
+            && str_starts_with(trim((string) $this->secret_key), 'sk_');
+    }
+}