fix issue

apps/edr-freight-web/backoffice/src/components/trainScheduling/ScheduleWorkspacePanel.tsx

@@ -95,7 +95,13 @@ function usedWeight(schedule: TrainScheduleDetail): number {
   );
 }
 
-/** Max pull weight across all locomotives on the set (0 when unknown). */
+/**
+ * Pull capacity of the set = the WEAKEST locomotive's max pull weight (0 when
+ * unknown). The API caps at the weakest loco, not the sum of all locos — a
+ * consist can only pull as hard as its weakest engine. Note: the API also adds
+ * the consist tare to the used weight when it checks this cap; tare isn't
+ * available client-side, so this meter compares cargo-only load against pull.
+ */
 function pullCapacity(schedule: TrainScheduleDetail): number {
   const set = schedule.trainSet;
   if (!set) return 0;
@@ -105,7 +111,8 @@ function pullCapacity(schedule: TrainScheduleDetail): number {
       : set.locomotive
         ? [set.locomotive]
         : [];
-  return locos.reduce((sum, l) => sum + (Number(l.maxPullWeightTons) || 0), 0);
+  if (locos.length === 0) return 0;
+  return Math.min(...locos.map((l) => Number(l.maxPullWeightTons) || 0));
 }
 
 export function ScheduleWorkspacePanel({

apps/edr-freight-web/backoffice/src/components/wagons/AssignWagonDialog.tsx

@@ -19,7 +19,7 @@ export function AssignWagonDialog({ trainId }: { trainId: string }) {
   const { toast } = useToast();
 
   const available = (wagons ?? []).filter(
-    (w) => w.status === Freight.WagonStatus.Available || !w.trainId,
+    (w) => w.status === Freight.WagonStatus.Available && !w.trainId,
   );
 
   const yardLabelById = useMemo(

apps/edr-freight-web/backoffice/src/components/wagons/WagonYardWorkspaceModal.tsx

@@ -183,10 +183,22 @@ const WagonYardWorkspaceModal = ({ opened, onClose }: WagonYardWorkspaceModalPro
     return yardWagons.filter((w) => w.currentYardId === yardId && w.wagonTypeId === typeId);
   }, [yardWagons, yardId, typeId]);
 
-  const availableWagons = useMemo(() => matching.filter((w) => w.status === AVAILABLE), [matching]);
-  const assignedWagons = useMemo(() => matching.filter((w) => w.status === ASSIGNED), [matching]);
+  // Wagons coupled to a built train (trainId set) are managed through the
+  // train-builder flow — they can't be bulk-flipped or transferred here, so
+  // keep them out of the action pools and bucket them under "Other".
+  const availableWagons = useMemo(
+    () => matching.filter((w) => w.status === AVAILABLE && !w.trainId),
+    [matching],
+  );
+  const assignedWagons = useMemo(
+    () => matching.filter((w) => w.status === ASSIGNED && !w.trainId),
+    [matching],
+  );
   const otherWagons = useMemo(
-    () => matching.filter((w) => w.status !== AVAILABLE && w.status !== ASSIGNED),
+    () =>
+      matching.filter(
+        (w) => w.trainId != null || (w.status !== AVAILABLE && w.status !== ASSIGNED),
+      ),
     [matching],
   );
   const total = matching.length;

apps/edr-freight-web/backoffice/src/pages/fleet/FleetResourcePage.tsx

@@ -298,7 +298,17 @@ const FleetResourcePage = () => {
   const handleFormSubmit = async (values: Record<string, unknown>) => {
     try {
       if (editing && "id" in editing) {
-        await update.mutateAsync({ slug, id: String(editing.id), data: values });
+        // PATCH only the fields the user actually changed. Re-sending the whole
+        // form used to re-submit status/currentYardId on every save — which,
+        // for a locomotive/wagon coupled to a built train, silently diverged
+        // the consist (editing a name could move the loco to another yard).
+        const editingRecord = editing as unknown as Record<string, unknown>;
+        const changed = Object.fromEntries(
+          Object.entries(values).filter(
+            ([key, value]) => value !== editingRecord[key],
+          ),
+        );
+        await update.mutateAsync({ slug, id: String(editing.id), data: changed });
         toast({ title: `${config.entityLabel} updated` });
       } else {
         await create.mutateAsync({ slug, data: values });