fix(ui) : add lang=ts to script tags using TypeScript syntax

ComponentItem, PieceItem, and machine/[id] used 'as string' type
assertions but were missing lang="ts" on their script tags.

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

frontend/app/components/ComponentItem.vue

@@ -329,7 +329,7 @@
   </div>
 </template>
 
-<script setup>
+<script setup lang="ts">
 import { ref, watch, computed } from 'vue'
 import PieceItem from './PieceItem.vue'
 import DocumentUpload from './DocumentUpload.vue'

frontend/app/components/PieceItem.vue

@@ -314,7 +314,7 @@
   </div>
 </template>
 
-<script setup>
+<script setup lang="ts">
 import { reactive, ref, onMounted, watch, computed } from 'vue'
 import ConstructeurSelect from './ConstructeurSelect.vue'
 import ProductSelect from '~/components/ProductSelect.vue'

frontend/app/pages/machine/[id].vue

@@ -200,7 +200,7 @@
   </div>
 </template>
 
-<script setup>
+<script setup lang="ts">
 import { computed, ref, watch, onMounted } from 'vue'
 import { useRoute } from 'vue-router'
 import { useMachineDetailData } from '~/composables/useMachineDetailData'