Add Ladill POS v1 — register, Pay checkout, and commerce links.

Staff-facing counter register at pos.ladill.com with catalog cart, cash and
MoMo/card checkout via Ladill Pay, CRM timeline/import, invoice prefill, and
Merchant catalog import.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/Http/Controllers/Pos/Concerns/ScopesToAccount.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace App\Http\Controllers\Pos\Concerns;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Http\Request;
+
+trait ScopesToAccount
+{
+    protected function ownerRef(Request $request): string
+    {
+        $user = ladill_account() ?? $request->user();
+
+        return (string) $user->public_id;
+    }
+
+    protected function authorizeOwner(Request $request, Model $model): void
+    {
+        abort_unless($model->getAttribute('owner_ref') === $this->ownerRef($request), 404);
+    }
+}