✨ Add skills page with category grouping (Story 2.4)

- Enhance Skill model with getCurrentLevel() and ordered scope
- Update SkillController to group by category with translated labels
- Add level and project_count to SkillResource
- Create skill.ts types (Skill, SkillCategory, SkillsResponse)
- Create useFetchSkills composable
- Create SkillCard component with animated progress bar
- Implement competences.vue with:
  - Responsive grid (2/3/4 columns)
  - Category sections with icons
  - Stagger animations (respects prefers-reduced-motion)
  - Loading/error/empty states
  - Placeholder for vis.js skill tree (Epic 3)

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

frontend/app/pages/competences.vue

@@ -1,16 +1,153 @@
 <template>
-  <div class="min-h-screen p-8">
-    <h1 class="text-3xl font-narrative text-sky-text">{{ $t('pages.skills.title') }}</h1>
-    <p class="mt-4 text-sky-text/70">{{ $t('pages.skills.description') }}</p>
+  <div class="max-w-7xl mx-auto px-4 py-8 md:py-12">
+    <h1 class="text-3xl md:text-4xl font-ui font-bold text-sky-text mb-8">
+      {{ $t('skills.title') }}
+    </h1>
+
+    <!-- Loading state -->
+    <div v-if="pending" class="space-y-10">
+      <div v-for="i in 4" :key="i">
+        <div class="bg-sky-text/5 h-7 rounded w-32 mb-4" />
+        <div class="grid grid-cols-2 md:grid-cols-3 lg:grid-cols-4 gap-4">
+          <div v-for="j in 4" :key="j" class="bg-sky-text/5 rounded-xl h-28 animate-pulse" />
+        </div>
+      </div>
+    </div>
+
+    <!-- Error state -->
+    <div v-else-if="error" class="text-center py-16">
+      <p class="text-sky-text/60 font-narrative mb-6">
+        {{ $t('skills.load_error') }}
+      </p>
+      <button
+        class="px-6 py-3 bg-sky-accent text-sky-dark font-ui font-semibold rounded-lg hover:opacity-90 transition-opacity"
+        @click="refresh()"
+      >
+        {{ $t('common.retry') }}
+      </button>
+    </div>
+
+    <!-- Skills by category -->
+    <div v-else class="space-y-12">
+      <section
+        v-for="(category, categoryIndex) in categories"
+        :key="category.category"
+        class="category-section"
+        :style="{ '--category-delay': `${categoryIndex * 150}ms` }"
+      >
+        <h2 class="text-xl font-ui font-semibold text-sky-text mb-5 flex items-center gap-2">
+          <span class="text-sky-accent">{{ getCategoryIcon(category.category) }}</span>
+          {{ category.category_label }}
+        </h2>
+
+        <div class="grid grid-cols-2 md:grid-cols-3 lg:grid-cols-4 gap-4">
+          <FeatureSkillCard
+            v-for="(skill, skillIndex) in category.skills"
+            :key="skill.id"
+            :skill="skill"
+            class="skill-card-animated"
+            :style="{ '--animation-delay': `${categoryIndex * 150 + skillIndex * 60}ms` }"
+            @click="handleSkillClick"
+          />
+        </div>
+      </section>
+
+      <!-- Empty state -->
+      <div v-if="categories.length === 0" class="text-center py-16">
+        <p class="text-sky-text/60 font-narrative">
+          {{ $t('skills.no_skills') }}
+        </p>
+      </div>
+
+      <!-- Placeholder for vis.js skill tree (Epic 3) - Desktop only -->
+      <div class="hidden lg:block mt-12 p-8 border-2 border-dashed border-sky-text/10 rounded-xl text-center">
+        <p class="text-sky-text/40 font-narrative">
+          {{ $t('skills.skill_tree_placeholder') }}
+        </p>
+      </div>
+    </div>
   </div>
 </template>
 
 <script setup lang="ts">
-const { setPageMeta } = useSeo()
-const { t } = useI18n()
+import type { Skill } from '~/types/skill'
+import { useProgressionStore } from '~/stores/progression'
 
+const { t } = useI18n()
+const { setPageMeta } = useSeo()
+const store = useProgressionStore()
+
+const { data, pending, error, refresh } = await useFetchSkills()
+
+const categories = computed(() => data.value?.data ?? [])
+
+// SEO
 setPageMeta({
-  title: t('pages.skills.title'),
-  description: t('pages.skills.description'),
+  title: t('skills.page_title'),
+  description: t('skills.page_description'),
+})
+
+// Category icons
+const categoryIcons: Record<string, string> = {
+  frontend: '🎨',
+  backend: '⚙️',
+  tools: '🛠️',
+  soft_skills: '💡',
+}
+
+function getCategoryIcon(category: string): string {
+  return categoryIcons[category.toLowerCase()] ?? '📚'
+}
+
+// Handle skill click (preparation for Story 2.5)
+function handleSkillClick(skill: Skill) {
+  // Will be implemented in Story 2.5 - modal with related projects
+  console.log('Skill clicked:', skill.slug)
+}
+
+onMounted(() => {
+  store.visitSection('competences')
 })
 </script>
+
+<style scoped>
+.category-section {
+  animation: fadeIn 0.5s ease-out forwards;
+  animation-delay: var(--category-delay, 0ms);
+  opacity: 0;
+}
+
+.skill-card-animated {
+  animation: fadeInUp 0.4s ease-out forwards;
+  animation-delay: var(--animation-delay, 0ms);
+  opacity: 0;
+}
+
+@keyframes fadeIn {
+  from {
+    opacity: 0;
+  }
+  to {
+    opacity: 1;
+  }
+}
+
+@keyframes fadeInUp {
+  from {
+    opacity: 0;
+    transform: translateY(12px);
+  }
+  to {
+    opacity: 1;
+    transform: translateY(0);
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .category-section,
+  .skill-card-animated {
+    animation: none;
+    opacity: 1;
+  }
+}
+</style>