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

what:

- assign tax lines only to regular products

packages/modules/cart/src/migrations/.snapshot-medusa-cart.json

@@ -757,6 +757,16 @@
           "default": "true",
           "mappedType": "boolean"
         },
+        "is_giftcard": {
+          "name": "is_giftcard",
+          "type": "boolean",
+          "unsigned": false,
+          "autoincrement": false,
+          "primary": false,
+          "nullable": false,
+          "default": "false",
+          "mappedType": "boolean"
+        },
         "is_tax_inclusive": {
           "name": "is_tax_inclusive",
           "type": "boolean",

packages/modules/cart/src/migrations/Migration20250326151602.ts

@@ -0,0 +1,15 @@
+import { Migration } from "@mikro-orm/migrations"
+
+export class Migration20250326151602 extends Migration {
+  override async up(): Promise<void> {
+    this.addSql(
+      `alter table if exists "cart_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 "cart_line_item" drop column if exists "is_giftcard";`
+    )
+  }
+}

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

@@ -27,6 +27,7 @@ const LineItem = model
       variant_option_values: model.json().nullable(),
       requires_shipping: model.boolean().default(true),
       is_discountable: model.boolean().default(true),
+      is_giftcard: model.boolean().default(false),
       is_tax_inclusive: model.boolean().default(false),
       is_custom_price: model.boolean().default(false),
       compare_at_unit_price: model.bigNumber().nullable(),