Get a single menu with categories and items

{
    "data": {
        "menu_id": 101,
        "location_id": 42,
        "name": "Lunch Menu",
        "description": "Available weekdays 12-15",
        "language": "en",
        "template": "classic",
        "is_active": true,
        "created": "2026-01-15 10:30:00",
        "categories": [
            {
                "category_id": 201,
                "menu_id": 101,
                "name": "Starters",
                "description": "Light bites to begin your meal.",
                "is_visible": true,
                "sort_order": 1,
                "items": [
                    {
                        "item_id": 301,
                        "category_id": 201,
                        "menu_id": 101,
                        "name": "Margherita Pizza",
                        "description": "Fresh tomato, mozzarella, basil.",
                        "price": 12.5,
                        "photo_url": "https://pub-xxx.r2.dev/items/301.jpg",
                        "allergens": [
                            "gluten",
                            "milk"
                        ],
                        "dietary_tags": [
                            "vegetarian"
                        ],
                        "is_available": true,
                        "sort_order": 1,
                        "created": "2026-01-15 10:30:00"
                    }
                ]
            }
        ]
    }
}