`shop_locale.root_url` always returns current session's locale path instead of language-specific URL

Description

shop_locale.root_url inside a localization.available_countries / country.available_languages loop does not return the root URL for that language — it returns the root URL of the currently active locale for every iteration.

Liquid template:

{%- for country in localization.available_countries -%}
  "{{ country.iso_code }}": [
    {%- for lang in country.available_languages -%}
      {
        "iso_code": "{{ lang.iso_code }}",
        "endonym_name": {{ lang.endonym_name | json }},
        "root_url": {{ lang.root_url | json }}
      }{% unless forloop.last %},{% endunless %}
    {%- endfor -%}
  ]{% unless forloop.last %},{% endunless %}
{%- endfor -%}

Resulting output (truncated):

"AT": [
  {"iso_code": "de", "endonym_name": "Deutsch", "root_url": "/en-gb"},
  {"iso_code": "en", "endonym_name": "English", "root_url": "/en-gb"}
],
"DK": [
  {"iso_code": "da", "endonym_name": "Dansk",   "root_url": "/en-gb"},
  {"iso_code": "en", "endonym_name": "English", "root_url": "/en-gb"}
],
...

Every root_url is /en-gb — the path of the active session locale — regardless of which country or language is being iterated.

Expected behavior:

lang.root_url should return the root URL path for that specific language, e.g.:

"AT": [
  {"iso_code": "de", "endonym_name": "Deutsch",  "root_url": "/de"},
  {"iso_code": "en", "endonym_name": "English",  "root_url": "/en-gb"}
],
"DK": [
  {"iso_code": "da", "endonym_name": "Dansk",    "root_url": "/da"},
  {"iso_code": "en", "endonym_name": "English",  "root_url": "/en-gb"}
],

Impact:

This makes it impossible to build a reliable language/country switcher using localization.available_countries — the root_url property is unusable for any language other than the currently active one.

Environment:

• Reproduced on a live Shopify storefront with multiple market/language configurations
• Active locale at time of render: en-gb
• All other locales inherit the same /en-gb root URL

Start by locating the implementation of the localization language objects and the tests covering available countries, available languages, and root_url. Reproduce the supplied Liquid loop, then add regression coverage showing each language returns its own root path rather than the active locale’s path.