Implement translation fetching from Store API

[mdanilowicz]

Translations are currently not consistently fetched from the backend (Store API). There is no clearly defined or centralized mechanism for retrieving and hydrating translations during SSR and client-side navigation.

This issue proposes establishing a reliable translation-fetching strategy aligned with the Shopware Store API and Nuxt SSR lifecycle to ensure localized content is properly loaded and available CF.

Acceptance Criteria

• Translations are fetched from the Store API based on the active locale.
• SSR preloads translations and hydrates them on the client.