feat(workshop): allow admin/owner to delete service orders

- Soft-delete service orders via is_deleted flag.

- Added DELETE /pos/api/service-orders/<id> restricted to owner/admin.

- Updated list, detail, summary, status and assignment queries to exclude deleted orders.

- Added 'Eliminar orden' button in the detail modal for administrators.

pos/templates/workshop.html

@@ -15,7 +15,7 @@
   <meta name="theme-color" content="#F5A623" />
   <link rel="shortcut icon" type="image/png" href="/pos/static/pwa/icon-192.png" />
 
-  <link rel="stylesheet" href="/pos/static/css/workshop.css?v=34">
+  <link rel="stylesheet" href="/pos/static/css/workshop.css?v=35">
   <style>
     .so-notes-grid { display: grid; grid-template-columns: 120px 1fr; gap: var(--space-2); align-items: start; }
     .so-notes-grid .form-label { margin: 0; padding-top: var(--space-2); }
@@ -300,7 +300,7 @@
 <script src="/pos/static/js/pos-utils.js?v=33" defer></script>
 <script src="/pos/static/js/sidebar.js?v=33" defer></script>
 <script src="/pos/static/js/offline-banner.js" defer></script>
-<script src="/pos/static/js/workshop.js?v=34" defer></script>
+<script src="/pos/static/js/workshop.js?v=35" defer></script>
 <script>if('serviceWorker' in navigator){navigator.serviceWorker.register('/pos/sw.js',{scope:'/pos/'});}</script>
 <script src="/pos/static/js/pwa-install.js" defer></script>
 <script src="/pos/static/js/chat.js" defer></script>