Backend now supports per-session default currency

The backend now allows overriding the default currency per session, giving more flexibility in handling multi-currency environments.

• Previous behavior: The default currency was strictly tied to the domain and could not be changed.

• New behavior: While the default still comes from the domain’s admin configuration, it can now be overridden within the same domain using a new service endpoint.

Endpoint:

/api/service/currency/{CURRENCY_CODE}

Example: /api/service/currency/eur or /api/service/currency/sek

Once called, the selected currency is stored in the session, and the client will continue to use it for the duration of that session.

This enhancement is particularly useful for multi-regional stores or scenarios where customers need to switch currencies without moving between domains.