fix(ui) : phase 1 review fixes — machine context links, type annotations, double arrow

- Add ?from=machine&machineId=xxx query params to entity NuxtLinks in hierarchy
- Add useRoute + machineId computed to ComponentItem, PieceItem, MachineProductsCard
- Add :string type to confirmRemove* handlers in machine page
- Remove unicode arrow from DetailHeader backLabel (icon already provides it)
- Add !isEditMode guard on product links in MachineProductsCard

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

frontend/app/components/machine/MachineProductsCard.vue

@@ -30,8 +30,10 @@
           <div class="flex items-center justify-between flex-wrap gap-2">
             <p class="font-semibold" :class="product.pendingEntity ? 'text-error' : 'text-base-content'">
               <NuxtLink
-                v-if="!product.pendingEntity && product.id"
-                :to="`/product/${product.id}`"
+                v-if="!isEditMode && !product.pendingEntity && product.id"
+                :to="machineId
+                  ? { path: `/product/${product.id}`, query: { from: 'machine', machineId } }
+                  : `/product/${product.id}`"
                 class="hover:underline hover:text-primary transition-colors"
               >
                 {{ product.name }}
@@ -140,8 +142,11 @@
 </template>
 
 <script setup lang="ts">
-import { ref } from 'vue'
+import { ref, computed } from 'vue'
 import DocumentPreviewModal from '~/components/DocumentPreviewModal.vue'
+
+const route = useRoute()
+const machineId = computed(() => route.params.id as string | undefined)
 import { canPreviewDocument } from '~/utils/documentPreview'
 import {
   formatSize,