feat(promotion, dashboard, core-flows, cart, types, utils, medusa): tax inclusive promotions (#12412)

* feat: tax inclusive promotions

* feat: add a totals test case

* feat: add integration test

* chore: changeset

* fix: typo

* chore: refactor

* fix: tests

* fix: rest of buyget action tests

* fix: cart spec

* chore: expand integration test with item level totals

* feat: add a few more test cases

---------

Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>

packages/modules/cart/integration-tests/__tests__/services/cart-module/index.spec.ts

@@ -2913,6 +2913,7 @@ moduleIntegrationTestRunner<ICartModuleService>({
                 created_at: expect.any(String),
                 updated_at: expect.any(String),
                 item_id: expect.any(String),
+                is_tax_inclusive: false,
                 promotion_id: null,
                 deleted_at: null,
                 amount: 100,
@@ -3020,6 +3021,7 @@ moduleIntegrationTestRunner<ICartModuleService>({
                 created_at: expect.any(String),
                 updated_at: expect.any(String),
                 item_id: expect.any(String),
+                is_tax_inclusive: false,
                 promotion_id: null,
                 deleted_at: null,
                 amount: 200,