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/cart/src/models/line-item-adjustment.ts

@@ -9,6 +9,7 @@ const LineItemAdjustment = model
       description: model.text().nullable(),
       code: model.text().nullable(),
       amount: model.bigNumber(),
+      is_tax_inclusive: model.boolean().default(false),
       provider_id: model.text().nullable(),
       promotion_id: model.text().nullable(),
       metadata: model.json().nullable(),