feat: Allow customer metadata update (#9780)

* Allow customer metadata update 

See issue 9779
https://github.com/medusajs/medusa/issues/9779

* add integration tests for customer metadata

- Implemented integration tests to verify customer creation with metadata.

integration-tests/http/__tests__/customer/store/customer.spec.ts

@@ -53,6 +53,12 @@ medusaIntegrationTestRunner({
             email: "newcustomer@medusa.js",
             first_name: "John",
             last_name: "Doe",
+            metadata: {
+              loyalty_level: "gold",
+              preferences: {
+                newsletter: true,
+              },
+            },
           },
           {
             headers: {
@@ -69,6 +75,12 @@ medusaIntegrationTestRunner({
             first_name: "John",
             last_name: "Doe",
             has_account: true,
+            metadata: {
+              loyalty_level: "gold",
+              preferences: {
+                newsletter: true,
+              },
+            },
           }),
         })
       })

packages/medusa/src/api/store/customers/validators.ts

@@ -10,6 +10,7 @@ export const StoreCreateCustomer = z.object({
   first_name: z.string().nullish(),
   last_name: z.string().nullish(),
   phone: z.string().nullish(),
+  metadata: z.record(z.unknown()).nullish(),
 })
 
 export const StoreUpdateCustomer = z.object({
@@ -17,6 +18,7 @@ export const StoreUpdateCustomer = z.object({
   first_name: z.string().nullish(),
   last_name: z.string().nullish(),
   phone: z.string().nullish(),
+  metadata: z.record(z.unknown()).nullish(),
 })
 
 export const StoreGetCustomerAddressParams = createSelectParams()