`ValidSchema` check errors on nested translation keys

Describe the bug
When using the locales object in a section schema, Theme Check raises an error if the translation is an object rather than a string, despite being renderable on the frontend.

Despite this being accepted by the platform, and renderable by Liquid, in the /themes/:id/language UI the nested keys only use the last portion of the key (desktop or mobile) in this case. So whilst I'd argue this is still a valid schema, I do think it's still worth at least warning users about to discourage a poor edit experience for merchants.

Source

// section/test-section.liquid

<p>{{ 'sections.test-section.title' | t }}</p>
<p>{{ 'sections.test-section.description.desktop' | t }}</p>
<p>{{ 'sections.test-section.description.mobile' | t }}</p>

{% schema %}
{
  "name": "Section",
  "locales": {
    "en": {
      "title": "Title",
      "description": {
        "desktop": "Lorem ipsum dolor sit amet consectetur, adipisicing elit.",
        "mobile": "Lorem ipsum dolor sit amet"
      }
    }
  }
}
{% endschema %}

Expected behaviour
No errors

Actual behaviour
The description object in the schema has a ValidSchema error

Debugging information

• OS: Mac
• OS Version: Sequoia 15.2
• Theme Check Version: 3.73.2

Reproduce the ValidSchema error with the nested locales object from section/test-section.liquid, then locate the validation entry point that reports the description object. Compare the expected no-error behavior with the stated warning concern, and confirm the result against the same schema example.