feat(home): admin-managed homepage section manager (toggle/reorder/edit)

The homepage is now driven by a `home_layout` Website Setting (jsonb) instead of a
hardcoded section stack — zero backend changes, no migration.

- lib/home-layout.ts: section catalog + saved-layout merge + locale-aware config
  reader (`<field>_fa`/`<field>_en`) + public fetchHomeLayout() (falls back to
  defaults when unset/unreachable).
- app/[locale]/page.tsx: renders ordered, enabled sections from the layout, passing
  per-section content overrides.
- sections (Hero/Products/Templates/HowItWorks/Pricing/Testimonials/FAQ): accept an
  optional `config` prop overriding heading/subtitle/CTA, locale-aware, default-safe.
- new HomeSlides + HomeEvents sections render the previously-orphaned admin Slides
  (/v1/slides) and Home Events (/v1/home-events) data.
- admin: HomeSectionsManager (toggle on/off, ↑/↓ reorder, per-section FA/EN content
  editor) at /admin/home, saved via the existing /v1/settings upsert; nav item + i18n.

Verified: a saved layout overrides Hero/Pricing headings and reorders sections;
removing it reverts to the default homepage.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

messages/en.json

@@ -376,6 +376,7 @@
       "categories": "Categories",
       "tags": "Tags",
       "fonts": "Fonts",
+      "homePage": "Home Page",
       "blogs": "Blog",
       "learn": "Tutorials",
       "pages": "Pages",