🎉 Init monorepo Nuxt 4 + Laravel 12 (Story 1.1)

Setup complet de l'infrastructure projet :
- Frontend Nuxt 4 (SSR, TypeScript, i18n, Pinia, TailwindCSS)
- Backend Laravel 12 API-only avec middleware X-API-Key et CORS
- Design tokens (sky-dark, sky-accent, sky-text) et polices (Merriweather, Inter)
- Documentation planning et implementation artifacts

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

api/resources/js/bootstrap.js

@@ -0,0 +1,4 @@
+import axios from 'axios';
+window.axios = axios;
+
+window.axios.defaults.headers.common['X-Requested-With'] = 'XMLHttpRequest';