Nuxt i18n caching not working when loading locales via API

[sparrow-chik-chrk]

Environment

---

• Operating System: Windows_NT
• Node Version: v22.13.1
• Nuxt Version: 3.15.4
• CLI Version: 3.21.1
• Nitro Version: 2.10.4
• Package Manager: [email protected]
• Builder: -
• User Config: css, extends, devtools, fonts, future, hub, i18n, icon, image, modules, nitro, pages, primevue, runtimeConfig, strapi, swiper, typescript
• Runtime Modules: @primevue/[email protected], @nuxthub/[email protected], [email protected], @nuxt/[email protected], [email protected], @nuxtjs/[email protected]
• Build Modules: -

---

Reproduction

1. Configure nuxt.config.ts with lazy: true and API-based locale loading:

   export default defineNuxtConfig({
     i18n: {
    locales: [
      {
        code: 'en',
        language: 'en-US',
        files: [
          { path: 'en-US.ts', cache: true },
          { path: 'strapi.ts', cache: true },
        ],
      },
      {
        code: 'uk',
        language: 'uk-UA',
        files: [
          { path: 'uk-UA.ts', cache: true },
          { path: 'strapi.ts', cache: true },
        ],
      },
    ],
    lazy: true,
    ...
    },
   })

2. Use defineI18nLocale to fetch locale messages from an API:

      export default defineI18nLocale(async locale => {
        try {
          const res = await $fetch<{
            data?: SiteLocaleTextCollection[]
          }>(`/api/site-locale-texts?filters[locale_code][$eq]=${locale}`, {
            headers: {
              'Content-Type': 'application/json'
            }
          });
          return res.data?.length ? res.data.at(0)?.json : {};
        } catch (error) {
          console.warn(error);
          return {};
        }
      });

3. Switch between locales multiple times in the UI.

Describe the bug

When switching locales, Nuxt i18n sends a request to the server every time the locale changes, instead of using cached messages. According to the documentation, caching should be enabled by default for static files and configurable for API-loaded locales, but in this case, it seems to be ignored.

Expected behavior:
After the first request, the locale messages should be cached and reused instead of refetching them on every locale change.