🎨 Add ProjectCard component with hover effect (Story 2.1)

Reusable project card with NuxtImg lazy loading, hover overlay with
"Discover" CTA, responsive design, and full accessibility support
including prefers-reduced-motion.

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

frontend/i18n/fr.json

@@ -74,6 +74,11 @@
     "meta_title": "C\u00e9lian - D\u00e9veloppeur Full-Stack | CV Express",
     "meta_description": "D\u00e9veloppeur Full-Stack sp\u00e9cialis\u00e9 en Vue.js, Nuxt, Laravel. D\u00e9couvrez mon profil et mes projets en 30 secondes."
   },
+  "projects": {
+    "discover": "D\u00e9couvrir",
+    "no_projects": "Aucun projet pour le moment",
+    "view_all": "Voir tous les projets"
+  },
   "pages": {
     "projects": {
       "title": "Projets",