feat(inventory): add traceable cart stock reservations

tests/Feature/Cart/CartControllerTest.php

@@ -73,6 +73,11 @@ class CartControllerTest extends TestCase
             'id' => $item->inventory_id,
             'reserved_stock' => 2,
         ]);
+        $this->assertDatabaseHas('stock_reservations', [
+            'inventory_id' => $item->inventory_id,
+            'quantity' => 2,
+            'status' => 'active',
+        ]);
     }
 
     public function test_it_filters_item_images_when_the_tenant_disables_them(): void
@@ -129,6 +134,12 @@ class CartControllerTest extends TestCase
             'id' => $variant->inventory_id,
             'reserved_stock' => 5,
         ]);
+        $this->assertDatabaseHas('stock_reservations', [
+            'cart_item_id' => $response->json('data.items.0.id'),
+            'inventory_id' => $variant->inventory_id,
+            'quantity' => 5,
+            'status' => 'active',
+        ]);
     }
 
     public function test_authenticated_cart_respects_previous_purchases_and_repeated_additions(): void
@@ -283,6 +294,12 @@ class CartControllerTest extends TestCase
             'id' => $variant->inventory_id,
             'reserved_stock' => 0,
         ]);
+        $this->assertDatabaseHas('stock_reservations', [
+            'cart_item_id' => null,
+            'inventory_id' => $variant->inventory_id,
+            'quantity' => 0,
+            'status' => 'released',
+        ]);
     }
 
     public function test_it_changes_an_item_variant_and_moves_the_stock_reservation(): void