feat(core-flows,types,order,cart): assign tax lines only to regular products (#11994)

what:

- assign tax lines only to regular products

packages/modules/order/src/migrations/Migration20250326151554.ts

@@ -0,0 +1,15 @@
+import { Migration } from "@mikro-orm/migrations"
+
+export class Migration20250326151554 extends Migration {
+  override async up(): Promise<void> {
+    this.addSql(
+      `alter table if exists "order_line_item" add column if not exists "is_giftcard" boolean not null default false;`
+    )
+  }
+
+  override async down(): Promise<void> {
+    this.addSql(
+      `alter table if exists "order_line_item" drop column if exists "is_giftcard";`
+    )
+  }
+}

packages/modules/order/src/models/line-item.ts

@@ -22,6 +22,7 @@ const _OrderLineItem = model
     variant_title: model.text().nullable(),
     variant_option_values: model.json().nullable(),
     requires_shipping: model.boolean().default(true),
+    is_giftcard: model.boolean().default(false),
     is_discountable: model.boolean().default(true),
     is_tax_inclusive: model.boolean().default(false),
     compare_at_unit_price: model.bigNumber().nullable(),