feat: migre le site vers SvelteKit (Svelte 5, statique, zéro tiers)

- Rebuild complet SvelteKit 2 + Svelte 5 runes + TypeScript, adapter-static
- Images self-hébergées optimisées au build (vite-imagetools), fonts Archivo/Inter
  en woff2 local — BunnyCDN et Google Fonts supprimés (corrige les 403 d'images)
- Tokens charte OKI, thème sombre par défaut / clair opt-in, zéro emoji (set SVG)
- Motion : KineticText (stagger syncopé gwoka), ScrollProgressBar, View Transitions
- Village SVG isométrique pour les services hébergés + fallback accessible
- PWA (manifest + SW hors-ligne), 404 en KA, CSP nettoyée (.htaccess + _headers)
- Lighthouse mobile : 91/100/100/100 — JS initial 67 Ko gzip

src/lib/i18n/en/engagement.json

@@ -0,0 +1,25 @@
+{
+  "section_title": "Your project",
+  "section_title_accent": "starts here",
+  "section_subtitle": "Because every organisation deserves digital tools worthy of its ambitions",
+  "cards": [
+    {
+      "icon": "✊🏿",
+      "title": "Activist Associations",
+      "text": "A custom web application with preferential rates for your struggles",
+      "cta": "Contact us"
+    },
+    {
+      "icon": "🏛️",
+      "title": "Associations & Collectives",
+      "text": "Showcase site, member management, calendar, built for you",
+      "cta": "Contact us"
+    },
+    {
+      "icon": "💼",
+      "title": "Responsible Businesses",
+      "text": "Ethical digital presence, hosting independent from GAFAM",
+      "cta": "Contact us"
+    }
+  ]
+}