fix: add address and customer metadata to tax calc context (#10122)

Fixes CMRC-713

**What**
- Ensure that customer and shipping address metadata is passed in the tax calculation context when updating tax lines on a cart.

**Why**
- Gives more flexibility in criteria to evaluate tax rates. 
- https://github.com/medusajs/medusa/discussions/10121
- https://github.com/medusajs/medusa/discussions/10114

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

integration-tests/modules/__tests__/cart/store/cart.workflows.spec.ts

@@ -11,6 +11,7 @@ import {
   updateLineItemInCartWorkflow,
   updateLineItemsStepId,
   updatePaymentCollectionStepId,
+  updateTaxLinesWorkflow,
 } from "@medusajs/core-flows"
 import {
   ICartModuleService,
@@ -2159,6 +2160,44 @@ medusaIntegrationTestRunner({
           ])
         })
       })
+
+      describe("updateTaxLinesWorkflow", () => {
+        it("should include shipping address metadata in tax calculation context", async () => {
+          const cart = await cartModuleService.createCarts({
+            currency_code: "dkk",
+            region_id: defaultRegion.id,
+            shipping_address: {
+              metadata: {
+                testing_tax: true,
+              },
+            },
+            items: [
+              {
+                quantity: 1,
+                unit_price: 5000,
+                title: "Test item",
+              },
+            ],
+          })
+
+          const { transaction } = await updateTaxLinesWorkflow(
+            appContainer
+          ).run({
+            input: {
+              cart_id: cart.id,
+            },
+            throwOnError: false,
+          })
+
+          expect(
+            // @ts-ignore
+            transaction.context.invoke["use-remote-query"].output.output
+              .shipping_address.metadata
+          ).toEqual({
+            testing_tax: true,
+          })
+        })
+      })
     })
   },
 })

packages/core/core-flows/src/cart/workflows/update-tax-lines.ts

@@ -47,6 +47,7 @@ const cartFields = [
   "shipping_methods.amount",
   "customer.id",
   "customer.email",
+  "customer.metadata",
   "customer.groups.id",
   "shipping_address.id",
   "shipping_address.address_1",
@@ -56,6 +57,7 @@ const cartFields = [
   "shipping_address.country_code",
   "shipping_address.region_code",
   "shipping_address.province",
+  "shipping_address.metadata",
 ]
 
 export type UpdateTaxLinesWorkflowInput = {

packages/core/core-flows/src/tax/steps/get-item-tax-lines.ts

@@ -53,6 +53,7 @@ function normalizeTaxModuleContext(
     id: orderOrCart.customer.id,
     email: orderOrCart.customer.email,
     customer_groups: orderOrCart.customer.groups?.map((g) => g.id) || [],
+    metadata: orderOrCart.customer.metadata,
   }
 
   return {
@@ -63,6 +64,7 @@ function normalizeTaxModuleContext(
       address_2: address.address_2,
       city: address.city,
       postal_code: address.postal_code,
+      metadata: address.metadata,
     },
     customer,
     is_return: isReturn ?? false,

packages/core/types/src/tax/common.ts

@@ -448,6 +448,11 @@ export interface TaxCalculationContext {
      * The postal code.
      */
     postal_code?: string
+
+    /**
+     * Address metadata.
+     */
+    metadata?: Record<string, unknown> | null
   }
 
   /**
@@ -468,6 +473,11 @@ export interface TaxCalculationContext {
      * The groups that the customer belongs to.
      */
     customer_groups: string[]
+
+    /**
+     * Customer metadata.
+     */
+    metadata?: Record<string, unknown> | null
   }
 
   /**