feat: implement Telepagos webhook handling with request validation and service integration

app/Domains/Purchase/Models/Purchase.php

@@ -57,4 +57,33 @@ class Purchase extends Model
     {
         return $this->hasMany(PurchaseItem::class, 'compra_id');
     }
+
+    /**
+     * @return \Illuminate\Database\Eloquent\Relations\HasOne<TelepagosQr, $this>
+     */
+    public function telepagosQr()
+    {
+        return $this->hasOne(TelepagosQr::class, 'compra_id');
+    }
+
+    /**
+     * @return HasMany<TelepagosPayment, $this>
+     */
+    public function telepagosPayments(): HasMany
+    {
+        return $this->hasMany(TelepagosPayment::class, 'compra_id');
+    }
+
+    public function getTotalAmount(): float
+    {
+        return (float) $this->items()->sum('total');
+    }
+
+    public function finalize(): void
+    {
+        $this->update([
+            'status' => 'pagado', // Or the equivalent final status in your system
+            'payment_status' => 'paid',
+        ]);
+    }
 }