feat(): sync cart translation synced (medusajs#14226)

ref: medusajs#14189

  **Summary**

  This PR extends the translation module to support automatic translation syncing for cart line items based on the cart's locale.

  Key changes:
  - Added locale field to the Cart model to store the cart's locale preference
  - Created new workflow steps:
    - getTranslatedLineItemsStep - Translates line items when adding to cart or creating a cart
    - updateCartItemsTranslationsStep - Re-translates all cart items when the cart's locale changes
  - Integrated translation logic into cart workflows:
    - createCartWorkflow - Applies translations to initial line items
    - addToCartWorkflow - Applies translations when adding new items
    - updateCartWorkflow - Re-translates all items when locale_code is updated
    - refreshCartItemsWorkflow - Maintains translations during cart refresh
  - Added applyTranslationsToItems utility to map variant/product/type/collection translations to line item fields (title, subtitle, description, etc.)

Author: adrien2p

.changeset/dull-trains-shave.md

@@ -0,0 +1,9 @@
+---
+"@medusajs/medusa": patch
+"@medusajs/test-utils": patch
+"@medusajs/cart": patch
+"@medusajs/core-flows": patch
+"@medusajs/types": patch
+---
+
+feat(): sync cart translation synced