feat(pos): POS v2 feature parity + promote to default /pos

Completes the four POS v2 roadmap items:

1. Real split payments — split tab records N separate payment rows (equal split,
   last row takes the remainder), each row toggles Cash/Card; posts payments[].
2. Card-terminal push — confirmPay sums Card amounts and calls requestPosPayment
   (POS device) before recording; surfaces POS_DEVICE_* errors.
3. Customer + coupons + loyalty — reuses PosCustomerPicker (attach/search/create)
   and validates coupons via /coupons/validate (discount in totals). Pay sheet
   offers loyalty redemption (1 point = 100 toman) when a customer is attached.
4. Promote to default — /pos now renders POS v2 (full-screen, café-themed); the
   classic terminal moves to /pos-classic with its sidebar+topbar chrome. The
   "نسخه کلاسیک" link points there.

Order submission already carried customerId/guestName/guestPhone/couponId via the
shared cart store, so customer + coupon flow straight through send + pay.
tsc --noEmit clean.

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

web/dashboard/src/app/[locale]/(fullscreen)/pos-classic/layout.tsx

@@ -0,0 +1,50 @@
+"use client";
+
+import { useLocale } from "next-intl";
+import { Sidebar } from "@/components/layout/sidebar";
+import { Topbar } from "@/components/layout/topbar";
+import { CafeThemeProvider } from "@/components/theme/cafe-theme-provider";
+
+/**
+ * Classic POS route layout — wraps the terminal in the standard dashboard
+ * chrome (collapsible sidebar + topbar) but keeps the main content area
+ * overflow-hidden so PosScreen can manage its own internal scrolling.
+ */
+export default function PosClassicLayout({
+  children,
+}: {
+  children: React.ReactNode;
+}) {
+  const locale = useLocale();
+  const isRtl = locale !== "en";
+
+  const mainColumn = (
+    <div className="flex min-h-0 min-w-0 flex-1 flex-col">
+      <Topbar />
+      <main className="min-h-0 flex-1 overflow-hidden bg-background p-3 md:p-4">
+        {children}
+      </main>
+    </div>
+  );
+
+  return (
+    <CafeThemeProvider>
+      <div
+        className="flex h-screen min-h-0 overflow-hidden bg-background"
+        dir={isRtl ? "rtl" : "ltr"}
+      >
+        {isRtl ? (
+          <>
+            <Sidebar side="right" />
+            {mainColumn}
+          </>
+        ) : (
+          <>
+            <Sidebar side="left" />
+            {mainColumn}
+          </>
+        )}
+      </div>
+    </CafeThemeProvider>
+  );
+}

web/dashboard/src/app/[locale]/(fullscreen)/pos-classic/page.tsx

@@ -0,0 +1,12 @@
+import { Suspense } from "react";
+import { PosScreen } from "@/components/pos/pos-screen";
+
+/** Classic POS terminal — chrome (sidebar + topbar) is provided by layout.tsx.
+ *  Kept as a fallback while POS v2 (at /pos) is piloted. */
+export default function PosClassicPage() {
+  return (
+    <Suspense fallback={null}>
+      <PosScreen />
+    </Suspense>
+  );
+}

web/dashboard/src/app/[locale]/(fullscreen)/pos/layout.tsx

@@ -1,50 +1,13 @@
 "use client";
 
-import { useLocale } from "next-intl";
-import { Sidebar } from "@/components/layout/sidebar";
-import { Topbar } from "@/components/layout/topbar";
 import { CafeThemeProvider } from "@/components/theme/cafe-theme-provider";
 
 /**
- * POS route layout — wraps the terminal in the standard dashboard chrome
- * (collapsible sidebar + topbar) but keeps the main content area
- * overflow-hidden so PosScreen can manage its own internal scrolling.
+ * POS v2 layout — the redesigned terminal is full-screen (its own topbar +
+ * order ticket), so no dashboard sidebar/topbar chrome here. Café theming
+ * still applies. Auth guarding comes from the parent (fullscreen) layout.
+ * The classic POS keeps its chrome under /pos-classic.
  */
-export default function PosLayout({
-  children,
-}: {
-  children: React.ReactNode;
-}) {
-  const locale = useLocale();
-  const isRtl = locale !== "en";
-
-  const mainColumn = (
-    <div className="flex min-h-0 min-w-0 flex-1 flex-col">
-      <Topbar />
-      <main className="min-h-0 flex-1 overflow-hidden bg-background p-3 md:p-4">
-        {children}
-      </main>
-    </div>
-  );
-
-  return (
-    <CafeThemeProvider>
-      <div
-        className="flex h-screen min-h-0 overflow-hidden bg-background"
-        dir={isRtl ? "rtl" : "ltr"}
-      >
-        {isRtl ? (
-          <>
-            <Sidebar side="right" />
-            {mainColumn}
-          </>
-        ) : (
-          <>
-            <Sidebar side="left" />
-            {mainColumn}
-          </>
-        )}
-      </div>
-    </CafeThemeProvider>
-  );
+export default function PosLayout({ children }: { children: React.ReactNode }) {
+  return <CafeThemeProvider>{children}</CafeThemeProvider>;
 }

web/dashboard/src/app/[locale]/(fullscreen)/pos/page.tsx

@@ -1,11 +1,8 @@
-import { Suspense } from "react";
-import { PosScreen } from "@/components/pos/pos-screen";
+import { Pos2Screen } from "@/components/pos2/pos2-screen";
 
-/** POS terminal — chrome (sidebar + topbar) is provided by layout.tsx */
+/** Default POS terminal — redesigned v2, wired to live data (menu, tables,
+ *  orders, payments) via the shared cart store + offline submit pipeline.
+ *  The classic POS remains available at /[locale]/pos-classic. */
 export default function PosPage() {
-  return (
-    <Suspense fallback={null}>
-      <PosScreen />
-    </Suspense>
-  );
+  return <Pos2Screen />;
 }