Warranty polish: hero badges everywhere, search/pagination, re-check, shared apiError

- Shared utils/apiError.js reads the correct nested error message (with
  fallbacks); swept 37 views/components off the shallow path so real backend
  messages (e.g. in-use 409s) surface instead of generic "Failed".
- useWarrantyBadge composable: warranty hero status/end-date badge now on PC,
  equipment, printer, and network detail heroes (one shared fetch feeds the
  badge + the WarrantyPanel).
- Warranties list: client-side search (vendor/level/tag/asset) + pagination;
  truncate long service levels so they stop blowing out the table width.
- "Re-check all" button + POST /warranty/sync/dell?all=true to re-pull dated
  Dell warranties, not just missing ones.
- Deprecate the standalone pxe-images/warranty_sync.py in favor of the plugin.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend/src/components/AssetRelationships.vue

@@ -178,6 +178,7 @@ import { assetsApi, relationshipTypesApi } from '../api'
 import { colorStyle } from '@/utils/colorStyle'
 import { useAuthStore } from '../stores/auth'
 import { useToast } from '../composables/toast'
+import { apiError } from '../utils/apiError'
 const toast = useToast()
 
 const props = defineProps({
@@ -351,7 +352,7 @@ async function saveRelationship() {
     emit('updated')
   } catch (error) {
     console.error('Failed to create relationship:', error)
-    toast.error('Failed to create relationship: ' + (error.response?.data?.message || error.message))
+    toast.error(apiError(error, 'Failed to create relationship'))
   }
 }