feat(workflows-sdk,core-flows,medusa,types): add workflow to update promotions to cart (#6474)

what:

- adds API + workflow to add/remove promotions in a cart
- minor fixes in promotions module
- minor type fixes in cart module
- typing fix in workflows-sdk (Thanks @adrien2p)
- fix step result in workflows-sdk (Thanks @adrien2p)

RESOLVES CORE-1768

Co-authored-by: Adrien de Peretti <25098370+adrien2p@users.noreply.github.com>

packages/types/src/cart/common.ts

@@ -206,7 +206,7 @@ export interface CartShippingMethodDTO {
   /**
    * The price of the shipping method
    */
-  unit_price: number
+  amount: number
 
   /**
    * Whether the shipping method price is tax inclusive or not

packages/types/src/cart/service.ts

@@ -22,8 +22,8 @@ import {
 } from "./common"
 import {
   CreateAddressDTO,
-  CreateAdjustmentDTO,
   CreateCartDTO,
+  CreateLineItemAdjustmentDTO,
   CreateLineItemDTO,
   CreateLineItemForCartDTO,
   CreateLineItemTaxLineDTO,
@@ -185,14 +185,14 @@ export interface ICartModuleService extends IModuleService {
   ): Promise<LineItemAdjustmentDTO[]>
 
   addLineItemAdjustments(
-    data: CreateAdjustmentDTO[]
+    data: CreateLineItemAdjustmentDTO[]
   ): Promise<LineItemAdjustmentDTO[]>
   addLineItemAdjustments(
-    data: CreateAdjustmentDTO
+    data: CreateLineItemAdjustmentDTO
   ): Promise<LineItemAdjustmentDTO[]>
   addLineItemAdjustments(
     cartId: string,
-    data: CreateAdjustmentDTO[]
+    data: CreateLineItemAdjustmentDTO[]
   ): Promise<LineItemAdjustmentDTO[]>
 
   setLineItemAdjustments(