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/static/js/workshop.js

@@ -27,6 +27,7 @@ var Workshop = (function() {
     var hidePrices = role === 'workshop' || role === 'mechanic';
     var perms = user.permissions || [];
     var canEdit = role === 'owner' || role === 'admin' || perms.indexOf('workshop.edit') !== -1;
+    var canDelete = role === 'owner' || role === 'admin';
     var canSell = role === 'owner' || role === 'admin' || perms.indexOf('pos.sell') !== -1;
 
     var COLUMNS = [
@@ -413,6 +414,7 @@ var Workshop = (function() {
             '</div>' : '';
         footer.innerHTML = statusHtml +
             '<button class="btn btn--ghost" onclick="Workshop.closeDetailModal()">Cerrar</button>' +
+            (canDelete ? '<button class="btn btn--danger" onclick="Workshop.deleteOrder()">Eliminar orden</button>' : '') +
             '<button class="btn btn--secondary" onclick="Workshop.printOrder()">' +
             '<svg viewBox="0 0 24 24"><polyline points="6 9 6 2 18 2 18 9"/><path d="M6 18H4a2 2 0 0 1-2-2v-5a2 2 0 0 1 2-2h16a2 2 0 0 1 2 2v5a2 2 0 0 1-2 2h-2"/><rect x="6" y="14" width="12" height="8"/></svg>' +
             'Imprimir orden</button>' +
@@ -699,6 +701,18 @@ var Workshop = (function() {
         }).catch(function(e) { alert('Error: ' + e.message); });
     }
 
+    function deleteOrder() {
+        if (!currentOrderId) return;
+        if (!confirm('¿Eliminar esta orden de servicio? Se ocultará del taller pero las reservas de inventario y la venta asociada (si existe) no se verán afectadas.')) return;
+        api('DELETE', '/' + currentOrderId, {})
+            .then(function() {
+                closeDetailModal();
+                loadSummary();
+                loadOrders();
+            })
+            .catch(function(e) { alert('Error: ' + e.message); });
+    }
+
     function printOrder() {
         if (!currentOrderId) return;
         if (!window.NexusPrinter || !window.NexusPrinter.isConnected()) {
@@ -907,6 +921,7 @@ var Workshop = (function() {
         addSelectedItem: addSelectedItem,
         addLabor: addLabor,
         convertToSale: convertToSale,
+        deleteOrder: deleteOrder,
         printOrder: printOrder,
         openNewOrderModal: openNewOrderModal,
         closeNewOrderModal: closeNewOrderModal,