fix(types,order,medusa): Create credit lines + hooks (#11569)

what:

- api/workflows to create credit lines
- hooks to enable extending credit lines

packages/modules/order/src/utils/actions/credit-line-add.ts

@@ -1,26 +1,36 @@
-import { ChangeActionType, MedusaError } from "@medusajs/framework/utils"
+import {
+  ChangeActionType,
+  MathBN,
+  MedusaError,
+} from "@medusajs/framework/utils"
+import { CreateOrderCreditLineDTO, OrderCreditLineDTO } from "@medusajs/types"
 import { OrderChangeProcessing } from "../calculate-order-change"
 import { setActionReference } from "../set-action-reference"
 
 OrderChangeProcessing.registerActionType(ChangeActionType.CREDIT_LINE_ADD, {
   operation({ action, currentOrder, options }) {
-    const creditLines = currentOrder.credit_lines ?? []
-    let existing = creditLines.find((cl) => cl.id === action.reference_id)
+    const creditLines: (OrderCreditLineDTO | CreateOrderCreditLineDTO)[] =
+      currentOrder.credit_lines ?? []
+    const existing = creditLines.find(
+      (cl) => "id" in cl && cl?.id === action.reference_id
+    )
 
-    if (!existing) {
-      const newCreditLine = {
-        order_id: currentOrder.id,
-        amount: action.amount!,
-        reference: action.reference,
-        reference_id: action.reference_id,
-      }
-
-      creditLines.push(newCreditLine as any)
-
-      setActionReference(newCreditLine, action, options)
-
-      currentOrder.credit_lines = creditLines
+    if (existing) {
+      return
     }
+
+    const newCreditLine = {
+      order_id: currentOrder.id,
+      amount: MathBN.convert(action.amount!),
+      reference: action.reference!,
+      reference_id: action.reference_id!,
+    }
+
+    creditLines.push(newCreditLine)
+
+    setActionReference(newCreditLine, action, options)
+
+    currentOrder.credit_lines = creditLines
   },
   validate({ action }) {
     if (action.amount == null) {