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.

packages/ui-common/package.json

@@ -7,6 +7,7 @@
   "types": "./src/index.ts",
   "exports": {
     ".": "./src/index.ts",
+    "./display-timezone": "./src/lib/display-timezone.ts",
     "./styles.css": "./dist/index.css",
     "./theme.css": "./src/styles/theme.css"
   },

packages/ui-common/src/lib/display-timezone.ts

@@ -0,0 +1,48 @@
+/**
+ * Side-effect module: pins every Intl-based date/time display to East Africa
+ * Time (UTC+3) so all users see the same wall-clock times no matter what
+ * timezone their PC is set to. Import it FIRST in the app entry, before any
+ * other app module, so no module-scope formatter is created unpatched:
+ *
+ *   import "@edr/ui-common/display-timezone";
+ *
+ * Call sites that pass an explicit `timeZone` option keep it. date-fns and
+ * dayjs `format()` do NOT go through Intl and stay PC-local — don't use them
+ * to display API timestamps.
+ */
+export const DISPLAY_TIME_ZONE = "Africa/Addis_Ababa";
+
+type Locales = string | string[] | undefined;
+type LocaleMethod = (
+  this: Date,
+  locales?: Locales,
+  options?: Intl.DateTimeFormatOptions,
+) => string;
+
+function pinned(original: LocaleMethod): LocaleMethod {
+  return function (locales, options) {
+    return original.call(this, locales, {
+      ...options,
+      timeZone: options?.timeZone ?? DISPLAY_TIME_ZONE,
+    });
+  };
+}
+
+Date.prototype.toLocaleString = pinned(Date.prototype.toLocaleString);
+Date.prototype.toLocaleDateString = pinned(Date.prototype.toLocaleDateString);
+Date.prototype.toLocaleTimeString = pinned(Date.prototype.toLocaleTimeString);
+
+const OriginalDateTimeFormat = Intl.DateTimeFormat;
+function PinnedDateTimeFormat(
+  locales?: Locales,
+  options?: Intl.DateTimeFormatOptions,
+): Intl.DateTimeFormat {
+  return new OriginalDateTimeFormat(locales, {
+    ...options,
+    timeZone: options?.timeZone ?? DISPLAY_TIME_ZONE,
+  });
+}
+// Keep `instanceof Intl.DateTimeFormat` and the static method working.
+PinnedDateTimeFormat.prototype = OriginalDateTimeFormat.prototype;
+PinnedDateTimeFormat.supportedLocalesOf = OriginalDateTimeFormat.supportedLocalesOf;
+Intl.DateTimeFormat = PinnedDateTimeFormat as unknown as typeof Intl.DateTimeFormat;