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

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

packages/modules/promotion/src/models/promotion.ts

@@ -8,6 +8,7 @@ const Promotion = model
     id: model.id({ prefix: "promo" }).primaryKey(),
     code: model.text().searchable(),
     is_automatic: model.boolean().default(false),
+    is_tax_inclusive: model.boolean().default(false),
     type: model.enum(PromotionUtils.PromotionType).index("IDX_promotion_type"),
     status: model
       .enum(PromotionUtils.PromotionStatus)