French docs sidebar shows English section labels #1793

On the French docs pages, the sidebar's section headings are in English: "Tutorials", "Reference", "Changelog" and "Runtime Core API". The sidebar groups in astro.config.ts set only label, with no translations, so Starlight shows the same string in every locale. The French home page names the same sections "Tutoriels" and "Référence", and every other piece of Starlight chrome on those pages is French ("Sur cette page", "Suivant"). A French reader sees the page call the section "Référence" while the sidebar beside it says "Reference". (The pages inside these sections are English-only by design, docs/AGENTS.md; this concerns only the navigation labels.)

Where

apps/outreach/astro.config.ts:79-102 (excerpt):

{
  autogenerate: { directory: 'docs/2-tutorials' },
  label: 'Tutorials'
},
...
{
  autogenerate: { directory: 'docs/5-reference' },
  label: 'Reference'
},
{
  label: 'Changelog',
  slug: 'docs/changelog'
},

and :71-74, the typedoc group:

sidebar: {
  collapsed: true,
  label: 'Runtime Core API'
},

docs/fr/1-introduction/1.0-home.md names them "Tutoriels (en anglais)" and "Référence (en anglais)".

Reproduce

1. Open https://opendatacapture.org/fr/docs/introduction/home/.
2. Read the sidebar group headings.

Actual: "Introduction, Tutorials, Guides, Concepts, Reference, Changelog, Runtime Core API".
Expected: "Introduction, Tutoriels, Guides, Concepts, Référence, Journal des modifications, API de Runtime Core", matching the French home page.

Tests

apps/outreach has no unit or Playwright suite, by decision (apps/outreach/AGENTS.md). Verify through the build: the sidebar in dist/fr/docs/introduction/home/index.html shows the French labels, and the English pages are unchanged.

Suggested fix

Add translations: { fr: '…' } to the Tutorials, Reference and Changelog sidebar entries, which Starlight supports on both groups and links. For the typedoc group, add a translations field to StarlightTypeDocSidebarOptions and pass it through in getSidebarGroupFromPackageReflections/getSidebarGroupFromReflections.