Keep the last run a batch order can re-queue a plate from

An order produces what it still owes by cloning an existing queue item for
the same plate. That row is the only record of the printer target, AMS
mapping and print options the user chose, so deleting the last one left the
order reporting work outstanding that nothing could produce, and no way to
close it out: Cancel was hidden unless there were pending items to cancel,
which by then there were none.

Deleting an order's last surviving run for a plate now cancels it instead.
A cancelled run does not satisfy a target, so the order still owes the print
and can still make it. A completed run is exempt and still deletes outright
-- rewriting it as cancelled would falsify what the order produced.

Also: the response reports per plate whether anything is left to clone, so
the card explains a stranded plate rather than offering a button that can
only fail; dispatch skips a stranded plate instead of aborting the whole
order; and Cancel is offered for any active order.

frontend/src/components/BatchOrdersView.tsx

@@ -163,6 +163,9 @@ function BatchOrderCard({
   const denominator = batch.has_targets ? batch.target_count : batch.completed_count + batch.pending_count
     + batch.printing_count + batch.failed_count;
   const percent = denominator > 0 ? Math.round((batch.completed_count / denominator) * 100) : 0;
+  // Runs the order owes that nothing can produce any more: their plate's last
+  // queue item was deleted, so there is no configuration left to clone (#2960).
+  const strandedCount = batch.has_targets ? batch.remaining_count - batch.dispatchable_count : 0;
   const dueDate = batch.due_date ? parseUTCDate(batch.due_date) : null;
   const isOverdue = dueDate != null && batch.status === 'active' && dueDate.getTime() < Date.now();
 
@@ -199,13 +202,17 @@ function BatchOrderCard({
         </div>
 
         <div className="flex items-center gap-2 flex-shrink-0">
-          {batch.has_targets && batch.remaining_count > 0 && batch.status !== 'cancelled' && canDispatch && (
+          {batch.has_targets && batch.dispatchable_count > 0 && batch.status !== 'cancelled' && canDispatch && (
             <Button variant="primary" size="sm" onClick={() => onDispatch()} disabled={isDispatching}>
               <PlayCircle className="w-4 h-4 mr-1" />
-              {t('queue.batchOrders.dispatchRemaining', { count: batch.remaining_count })}
+              {t('queue.batchOrders.dispatchRemaining', { count: batch.dispatchable_count })}
             </Button>
           )}
-          {batch.status === 'active' && batch.pending_count > 0 && canCancel && (
+          {/* Cancel is the only way to close an order out, so it must not be
+              gated on there being pending items to cancel: an order whose runs
+              were all deleted has none, and is exactly the one that needs
+              closing (#2960). */}
+          {batch.status === 'active' && canCancel && (
             <Button variant="ghost" size="sm" onClick={onCancel}>
               <XCircle className="w-4 h-4 mr-1" />
               {t('queue.cancelBatch')}
@@ -265,6 +272,13 @@ function BatchOrderCard({
         )}
       </div>
 
+      {strandedCount > 0 && batch.status !== 'cancelled' && (
+        <p className="flex items-start gap-1.5 text-xs text-orange-600 dark:text-orange-400 mb-1">
+          <AlertTriangle className="w-3 h-3 mt-0.5 flex-shrink-0" />
+          <span>{t('queue.batchOrders.strandedNotice', { runs: strandedCount, owed: batch.remaining_count })}</span>
+        </p>
+      )}
+
       {batch.has_targets && batch.plates.length > 0 && (
         <div className="mt-3 border-t border-bambu-dark-tertiary pt-3 space-y-1.5">
           {batch.plates.map((plate) => (
@@ -328,15 +342,21 @@ function PlateRow({
           <span className="text-bambu-gray">
             {t('queue.batchOrders.remaining', { count: plate.remaining })}
           </span>
-          {canDispatch && (
-            <button
-              type="button"
-              onClick={onDispatch}
-              disabled={isDispatching}
-              className="text-bambu-green hover:underline disabled:opacity-50"
-            >
-              {t('queue.batchOrders.dispatchPlate')}
-            </button>
+          {!plate.can_dispatch ? (
+            <span className="text-orange-600 dark:text-orange-400">
+              {t('queue.batchOrders.strandedPlate')}
+            </span>
+          ) : (
+            canDispatch && (
+              <button
+                type="button"
+                onClick={onDispatch}
+                disabled={isDispatching}
+                className="text-bambu-green hover:underline disabled:opacity-50"
+              >
+                {t('queue.batchOrders.dispatchPlate')}
+              </button>
+            )
           )}
         </span>
       )}