feat(events): associate purchases and integrations with events

app/Domains/Commerce/Purchase/Resources/PurchaseResource.php

@@ -36,11 +36,11 @@ class PurchaseResource extends JsonResource
                 === StorefrontWebsiteType::CHECKOUT_SUMMARY_EVENT;
         /** @var Event|null $checkoutEvent */
         $checkoutEvent = $usesEventSummary
-            ? $items
+            ? ($this->event ?? $items
                 ->map(fn (PurchaseItem $item) => $item->sourceCatalogItem?->event)
                 ->filter()
                 ->unique('id')
-                ->first()
+                ->first())
             : null;
 
         $subtotal = $items->isNotEmpty()
@@ -62,6 +62,7 @@ class PurchaseResource extends JsonResource
         return [
             'id' => $this->id,
             'cart_id' => $this->cart_id,
+            'event_id' => $this->event_id,
             'tenant_codigo' => $this->tenant_codigo,
             'user_id' => $this->user_id,
             'created_at' => $this->created_at,