✨ 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/components/feature/SkillCard.vue

@@ -0,0 +1,83 @@
+<template>
+  <button
+    type="button"
+    class="skill-card group w-full text-left bg-sky-text/5 rounded-xl p-4 hover:bg-sky-text/10 transition-colors cursor-pointer border border-sky-text/10"
+    @click="emit('click', skill)"
+  >
+    <div class="flex items-center gap-3 mb-3">
+      <!-- Icon -->
+      <div class="w-10 h-10 flex items-center justify-center bg-sky-dark/50 rounded-lg shrink-0">
+        <span v-if="skill.icon" class="text-2xl">{{ skill.icon }}</span>
+        <span v-else class="text-sky-text/40 text-lg">💻</span>
+      </div>
+
+      <!-- Name and project count -->
+      <div class="flex-1 min-w-0">
+        <h3 class="font-ui font-medium text-sky-text truncate group-hover:text-sky-accent transition-colors">
+          {{ skill.name }}
+        </h3>
+        <p v-if="skill.project_count" class="text-xs text-sky-text/50">
+          {{ skill.project_count }} {{ skill.project_count > 1 ? $t('skills.projects') : $t('skills.project') }}
+        </p>
+      </div>
+    </div>
+
+    <!-- Progress bar -->
+    <div class="relative h-2 bg-sky-dark/50 rounded-full overflow-hidden">
+      <div
+        class="skill-progress absolute left-0 top-0 h-full bg-gradient-to-r from-sky-accent to-sky-accent/80 rounded-full"
+        :style="{ '--target-width': `${progressPercent}%` }"
+      />
+    </div>
+
+    <!-- Level display -->
+    <div class="flex justify-between items-center mt-2">
+      <span class="text-xs text-sky-text/40 font-ui">{{ $t('skills.level') }}</span>
+      <span class="text-sm font-ui font-medium text-sky-accent">
+        {{ skill.level }}/{{ skill.max_level }}
+      </span>
+    </div>
+  </button>
+</template>
+
+<script setup lang="ts">
+import type { Skill } from '~/types/skill'
+
+const props = defineProps<{
+  skill: Skill
+}>()
+
+const emit = defineEmits<{
+  click: [skill: Skill]
+}>()
+
+const progressPercent = computed(() =>
+  Math.round((props.skill.level / props.skill.max_level) * 100),
+)
+</script>
+
+<style scoped>
+.skill-card:focus-visible {
+  outline: 2px solid var(--color-sky-accent, #38bdf8);
+  outline-offset: 2px;
+}
+
+.skill-progress {
+  width: 0;
+  animation: fillProgress 0.8s ease-out forwards;
+  animation-delay: var(--animation-delay, 0ms);
+}
+
+@keyframes fillProgress {
+  to {
+    width: var(--target-width, 0%);
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .skill-progress {
+    animation: none;
+    width: var(--target-width, 0%);
+  }
+}
+</style>