feat(versioning) : add entity versioning frontend with restore flow

- useEntityVersions composable (list, preview, restore API calls)
- EntityVersionList component with auto-refresh after save
- VersionRestoreModal with context-aware messages per entity type
- Integrate into machine, composant, piece, product detail pages
- Add restore action label to historyDisplayUtils
- Show structure slots in composant/piece consultation mode

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/components/common/EntityVersionList.vue

@@ -0,0 +1,151 @@
+<template>
+  <section class="space-y-3 rounded-lg border border-base-200 bg-base-200/40 p-4">
+    <header class="flex items-center justify-between gap-3">
+      <div>
+        <h2 class="font-semibold text-base-content">Versions</h2>
+        <p class="text-xs text-base-content/70">
+          Historique des versions avec possibilite de restauration.
+        </p>
+      </div>
+      <span v-if="versions.length" class="badge badge-outline">
+        {{ versions.length }} version{{ versions.length > 1 ? 's' : '' }}
+      </span>
+    </header>
+
+    <div v-if="loading" class="flex items-center gap-2 text-sm text-base-content/70">
+      <span class="loading loading-spinner loading-sm" aria-hidden="true" />
+      Chargement des versions...
+    </div>
+
+    <div v-else-if="error" class="alert alert-warning">
+      <span>{{ error }}</span>
+    </div>
+
+    <p v-else-if="versions.length === 0" class="text-xs text-base-content/70">
+      Aucune version enregistree.
+    </p>
+
+    <ul v-else class="max-h-96 space-y-2 overflow-y-auto pr-1">
+      <li
+        v-for="entry in versions"
+        :key="entry.version"
+        class="flex items-center justify-between rounded-md border border-base-200 bg-base-100 px-3 py-2"
+      >
+        <div class="min-w-0 flex-1">
+          <div class="flex items-center gap-2">
+            <span class="font-mono text-sm font-semibold">v{{ entry.version }}</span>
+            <span
+              v-if="entry.version === currentVersion"
+              class="badge badge-primary badge-sm"
+            >
+              actuelle
+            </span>
+            <span
+              v-if="entry.action === 'restore'"
+              class="badge badge-warning badge-sm"
+            >
+              restauration
+            </span>
+          </div>
+          <div class="mt-0.5 flex flex-wrap items-center gap-2 text-xs text-base-content/60">
+            <span>{{ actionLabel(entry.action) }}</span>
+            <span>&middot;</span>
+            <span>{{ formatDate(entry.createdAt) }}</span>
+            <span v-if="entry.actor">&middot; {{ entry.actor.label }}</span>
+          </div>
+        </div>
+        <button
+          v-if="canRestore && entry.version !== currentVersion"
+          class="btn btn-ghost btn-xs"
+          :disabled="restoring"
+          @click="handleRestore(entry.version)"
+        >
+          Restaurer
+        </button>
+      </li>
+    </ul>
+
+    <VersionRestoreModal
+      :visible="modalVisible"
+      :preview="previewData"
+      :restoring="restoring"
+      :field-labels="fieldLabels"
+      :entity-type="entityType"
+      @close="modalVisible = false"
+      @confirm="confirmRestore"
+    />
+  </section>
+</template>
+
+<script setup lang="ts">
+import { ref, computed, onMounted, watch, toRef } from 'vue'
+import { useEntityVersions, type RestorePreview } from '~/composables/useEntityVersions'
+import { usePermissions } from '~/composables/usePermissions'
+import { formatHistoryDate, historyActionLabel } from '~/shared/utils/historyDisplayUtils'
+import VersionRestoreModal from './VersionRestoreModal.vue'
+
+const props = defineProps<{
+  entityType: 'machine' | 'composant' | 'piece' | 'product'
+  entityId: string
+  fieldLabels: Record<string, string>
+  /** Increment this value to force a refresh of the versions list */
+  refreshKey?: number
+}>()
+
+const emit = defineEmits<{
+  restored: []
+}>()
+
+const { canEdit } = usePermissions()
+const canRestore = computed(() => canEdit.value)
+
+const { versions, loading, error, fetchVersions, fetchPreview, restore } = useEntityVersions({
+  entityType: props.entityType,
+  entityId: props.entityId,
+})
+
+const currentVersion = computed(() => {
+  if (versions.value.length === 0) return null
+  return versions.value[0]?.version ?? null
+})
+
+const modalVisible = ref(false)
+const previewData = ref<RestorePreview | null>(null)
+const restoring = ref(false)
+const targetVersion = ref<number | null>(null)
+
+const actionLabel = (action: string) => historyActionLabel(action)
+const formatDate = (date: string) => formatHistoryDate(date)
+
+const handleRestore = async (version: number) => {
+  targetVersion.value = version
+  previewData.value = null
+  modalVisible.value = true
+  previewData.value = await fetchPreview(version)
+}
+
+const confirmRestore = async () => {
+  if (!targetVersion.value) return
+  restoring.value = true
+  const result = await restore(targetVersion.value)
+  restoring.value = false
+  if (result?.success) {
+    modalVisible.value = false
+    await fetchVersions()
+    emit('restored')
+  }
+  else {
+    error.value = 'La restauration a echoue.'
+    modalVisible.value = false
+  }
+}
+
+onMounted(() => {
+  fetchVersions()
+})
+
+// Auto-refresh when parent signals a data change
+watch(toRef(props, 'refreshKey'), () => {
+  fetchVersions()
+})
+</script>