feat(print): separate kitchen & bar printers via print stations UI

The print engine already routed items to per-station printers (MenuCategory →
KitchenStation.PrinterIp, falling back to the branch kitchen printer) and prints
the customer receipt to the receipt printer — but there was no UI to set it up.
This exposes it:

- Settings → "Kitchen & bar printers": create/edit/delete print stations, each
  with its own printer IP/port, with a per-station test print (gated by
  ManageKitchenStations).
- Menu category editor: a "Print station" dropdown to route each category to a
  station (food → Kitchen, drinks → Bar); no station = branch kitchen printer.

Result: kitchen and bar tickets print on separate printers, while the customer
factor/receipt keeps printing on the receipt printer. fa/en/ar strings added.
No backend/migration changes — purely wiring the existing capability.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

web/dashboard/messages/en.json

@@ -348,7 +348,23 @@
     "configurePrinters": "Open printer settings",
     "posDeviceSection": "Card POS terminal",
     "posDeviceHint": "On card payment, the amount is sent via HTTP (POST /pay) to the device on your LAN.",
-    "posDeviceIp": "POS device IP address"
+    "posDeviceIp": "POS device IP address",
+    "testSent": "Test sent to the printer.",
+    "stations": {
+      "title": "Kitchen & bar print stations",
+      "subtitle": "Give each prep area its own printer and route menu categories to it.",
+      "help": "Create a station (e.g. Kitchen, Bar) with its own printer, then in Menu set each category’s print station — food → Kitchen, drinks → Bar. Items in a category with no station fall back to the branch kitchen printer. The customer receipt always prints to the receipt printer.",
+      "add": "Add station",
+      "name": "Station name",
+      "namePlaceholder": "e.g. Kitchen, Bar",
+      "printerIp": "Printer IP",
+      "noPrinter": "No printer — uses the kitchen printer",
+      "categoryCount": "{count} categories",
+      "test": "Test",
+      "empty": "No stations yet. Add Kitchen and Bar to print their items separately.",
+      "deleteConfirm": "Delete station “{name}”? Its categories will fall back to the kitchen printer.",
+      "saveError": "Failed to save the station."
+    }
   },
   "receipt": {
     "table": "Table",
@@ -907,6 +923,8 @@
     "newItem": "New item",
     "newCategory": "New category",
     "editCategoryTitle": "Edit category",
+    "printStation": "Print station",
+    "printStationNone": "Kitchen printer (default)",
     "close": "Close",
     "saving": "Saving…",
     "model3d": "3D model",
@@ -1275,6 +1293,7 @@
       "shopNotifications": "Notifications & sound",
       "printer": "Printer",
       "printerSettings": "Printer settings",
+      "printerStations": "Kitchen & bar printers",
       "printTest": "Print test page",
       "shopDiscover": "Discover & AI",
       "team": "Team & Staff",