How can i get current stock from the Shopify Buy SDK?

I am using the shopify buy sdk: https://www.npmjs.com/package/shopify-buy

I would like to get the current number of items in a stock for a specific product. I can fetch product info like this:

var Client = require('shopify-buy');
const shopify = Client.buildClient({
    domain: REDACTED_SHOPIFY_DOMAIN,
    storefrontAccessToken: REDACTED_SHOPIFY_TOKEN
});
let product = await shopify.product.fetch(productId);

the product returns the following values:

  'attrs',           '__typename',
  'id',              'availableForSale',
  'createdAt',       'updatedAt',
  'descriptionHtml', 'description',
  'handle',          'productType',
  'title',           'vendor',
  'publishedAt',     'onlineStoreUrl',
  'options',         'images',
  'variants',        'type'

This does not include information about the stock.

On this page it shows there’s a value called "totalInventory" which is what i need, but this i think is a different SDK and mine doesn’t return that value: https://shopify.dev/docs/api/storefront/2023-04/objects/Product

I also went into my api app settings, and looked at the "Storefront API access scopes". I added one called unauthenticated_read_product_inventory which I thought would do it, but it still returns the same info.

I also tried to use the graphql client, which seems like another way to access the API.

async function getProductGraphql(productId) {
    const productsQuery = shopify.graphQLClient.query((root) => {
        root.addConnection('products', { args: { first: 10 } }, (product) => {
            product.add('title');
            //product.add('totalInventory');
        });
    });

    shopify.graphQLClient.send(productsQuery).then(({ model, data }) => {
        let productData = data.products.edges[0].node;
        console.log('got product', productData);
    });
}

It works if I just ask for the title, but if I try to get totalInventory it says "Error: No field of name "totalInventory" found on type "Product" in schema"

Any idea how I can get this info using this sdk?

EDIT: I am closer. I switched require to this, which gives you access to properties that arent included normally. It now succecssfully can tell me the totalInventory of products.

var Client = require('shopify-buy/index.unoptimized.umd');
    const productsQuery = shopify.graphQLClient.query((root) => {
        root.addConnection('products', { args: { first: 10 } }, (product) => {
            product.add('title');
            product.add('totalInventory');
        });
    });

    shopify.graphQLClient.send(productsQuery).then(({ model, data }) => {
        let productData = data?.products?.edges[0]?.node;
        console.log('got product', productData);
    });

The problem with this example is that it’s looking for a list of products, not a specific one. So I tried to modify the query to access product instead of products, which should let me search by ID:

const productsQuery = shopify.graphQLClient.query((root) => {
    root.addConnection('product', { args: { id: productId } }, (product) => {
        product.add('title');
        product.add('totalInventory');
    });
});

shopify.graphQLClient.send(productsQuery).then(({ model, data }) => {
    let productData = data?.products?.edges[0]?.node;
    console.log('got product', productData);
});

But this throws an error on "root.addConnection" that says Error: No field of name "pageInfo" found on type "Product" in schema, which I dont understand because I don’t say "pageInfo" anywhere…