add items per wagon map to cargo types and sync bulk rate units

- Implemented  in the  to manage the physical item capacity for each wagon type.
- Added a new migration to create the  column in the  table.
- Introduced  method in  to update rate units when cargo type unit of measure changes.
- Updated booking calculations to consider items per wagon for break-bulk cargo.
- Refactored various components to utilize the new items fit logic and ensure consistent date formatting across the application.
- Added tests for the new display timezone functionality to ensure consistent date/time representation across different user settings.

apps/edr-freight-web/backoffice/src/pages/ruleEngine/CargoTypesPage.tsx

@@ -58,10 +58,15 @@ interface CargoNode extends RuleEngineRecord {
   unitOfMeasure?: string | null;
   /** Wagon types that can carry this bulk cargo during scheduling; empty if unset. */
   wagonTypes?: { id: string; code?: string; name?: string }[];
+  /** PER_ITEM only: whole items that physically fit one wagon, keyed by wagon-type id. */
+  itemsPerWagonMap?: Record<string, number> | null;
   isActive?: boolean;
   displayOrder?: number;
 }
 
+/** Form-value prefix for the per-wagon-type items-fit inputs (PER_ITEM cargo). */
+const ITEMS_FIT_PREFIX = "itemsFit__";
+
 const str = (v: unknown): string => (v == null ? "" : String(v));
 const orderOf = (n: CargoNode): number => Number(n.displayOrder ?? 0);
 
@@ -131,15 +136,33 @@ const CargoTypesPage = () => {
 
   // Wagon-type options for the "Wagon types" picker (bulk cargo → allowed list).
   const { data: wagonTypeOptions } = useWagonTypeOptions(canCreate || canUpdate);
-  const formFields = useMemo<FormFieldDef[]>(
-    () =>
-      FORM_FIELDS.map((field) =>
-        field.name === "wagonTypeIds"
-          ? { ...field, options: wagonTypeOptions ?? [] }
-          : field,
-      ),
-    [wagonTypeOptions],
-  );
+  const formFields = useMemo<FormFieldDef[]>(() => {
+    const base = FORM_FIELDS.map((field) =>
+      field.name === "wagonTypeIds"
+        ? { ...field, options: wagonTypeOptions ?? [] }
+        : field,
+    );
+    // PER_ITEM cargo: one "items per wagon" input per SELECTED wagon type — how
+    // many whole items physically fit that wagon (floor space binds before
+    // tonnage). Shown only while the wagon type is picked; the API requires a
+    // fit for every selected type on PER_ITEM cargo.
+    const fitFields: FormFieldDef[] = (wagonTypeOptions ?? []).map((opt) => ({
+      name: `${ITEMS_FIT_PREFIX}${opt.value}`,
+      label: `Items per ${opt.label} wagon`,
+      type: "number",
+      required: true,
+      placeholder: "e.g. 4",
+      showIf: (values) =>
+        values.unitOfMeasure === "PER_ITEM" &&
+        Array.isArray(values.wagonTypeIds) &&
+        (values.wagonTypeIds as string[]).includes(opt.value),
+      getInitialValue: (record) =>
+        (record as CargoNode).itemsPerWagonMap?.[opt.value],
+    }));
+    const wagonTypesAt = base.findIndex((field) => field.name === "wagonTypeIds");
+    base.splice(wagonTypesAt + 1, 0, ...fitFields);
+    return base;
+  }, [wagonTypeOptions]);
 
   const [search, setSearch] = useState("");
   const [formMode, setFormMode] = useState<FormMode | null>(null);
@@ -203,7 +226,18 @@ const CargoTypesPage = () => {
   const countAtRoot = (childrenOf.get("__root__") ?? []).length;
 
   const handleSubmit = (values: Record<string, unknown>) => {
-    const payload: Record<string, unknown> = { ...values };
+    // Fold the per-wagon-type fit inputs into the API's map shape. Null when
+    // none are visible (not PER_ITEM) so an update clears stale fits.
+    const payload: Record<string, unknown> = {};
+    const itemsPerWagonMap: Record<string, number> = {};
+    for (const [key, value] of Object.entries(values)) {
+      if (key.startsWith(ITEMS_FIT_PREFIX)) {
+        itemsPerWagonMap[key.slice(ITEMS_FIT_PREFIX.length)] = Number(value);
+      } else {
+        payload[key] = value;
+      }
+    }
+    payload.itemsPerWagonMap = Object.keys(itemsPerWagonMap).length ? itemsPerWagonMap : null;
     // Add always attaches to the page we're on; edit keeps the node's parent.
     if (formMode?.kind === "create" && current) {
       payload.parentGroupId = current.id;