Next.js Commerce refresh. (#966)

We're making some updates to Next.js Commerce. Everything prior to this commit marks what we're calling [`v1`](https://github.com/vercel/commerce/releases/tag/v1) as a point in time to be able to reference and still use going into the future. The current architecture of Commerce is a multi-vendor, interoperable solution, including:

- [Shopify](https://shopify.vercel.store/)
- [Swell](https://swell.vercel.store/)
- [BigCommerce](https://bigcommerce.vercel.store/)
- [Vendure](https://vendure.vercel.store/)
- [Saleor](https://saleor.vercel.store/)
- [Ordercloud](https://ordercloud.vercel.store/)
- [Spree](https://spree.vercel.store/)
- [Kibo Commerce](https://kibocommerce.vercel.store/)
- [Commerce.js](https://commercejs.vercel.store/)
- [SalesForce Cloud Commerce](https://salesforce-cloud-commerce.vercel.store/)

All features can be toggled on or off, and it's easy to change between commerce providers. To support this, we needed to create a ["commerce metaframework"](d1d9e8c434/packages/commerce/new-provider.md) where providers could confirm to an API spec to add support for Next.js Commerce. While this worked and was successful for `v1`, we have different design goals and ambitions for `v2`.

**What You Need To Know**

- `v1` will not be updated moving forward. If you need to reference `v1`, you will still be able to clone and deploy the version tagged at this release.
- `v2` will be shifting to be a single provider vs. provider agnostic. Other providers are welcome to fork this repository and swap out the underlying `lib/` implementation that connects to the selected commerce provider (Shopify). This architecture was chosen to reduce the surface area of the codebase, remove the intermediate metaframework layer for provider-interoperability, and enable usage with the latest Next.js and React features.
- We will be sharing more about `v2` in the future as we continue to iterate before the marked release.

app/[page]/layout.tsx

@@ -0,0 +1,16 @@
+import Footer from 'components/layout/footer';
+import { Suspense } from 'react';
+
+export default function Layout({ children }: { children: React.ReactNode }) {
+  return (
+    <Suspense>
+      <div className="w-full bg-white dark:bg-black">
+        <div className="mx-8 max-w-2xl py-20 sm:mx-auto">
+          <Suspense>{children}</Suspense>
+        </div>
+      </div>
+      {/* @ts-expect-error Server Component */}
+      <Footer />
+    </Suspense>
+  );
+}

app/[page]/page.tsx

@@ -0,0 +1,56 @@
+import type { Metadata } from 'next';
+
+import Prose from 'components/prose';
+import { getPage } from 'lib/shopify';
+import { notFound } from 'next/navigation';
+
+export const runtime = 'edge';
+
+export const revalidate = 43200; // 12 hours in seconds
+
+export async function generateMetadata({
+  params
+}: {
+  params: { page: string };
+}): Promise<Metadata> {
+  const page = await getPage(params.page);
+
+  if (!page) return notFound();
+
+  return {
+    title: page.seo?.title || page.title,
+    description: page.seo?.description || page.bodySummary,
+    openGraph: {
+      images: [
+        {
+          url: `/api/og?title=${encodeURIComponent(page.title)}`,
+          width: 1200,
+          height: 630
+        }
+      ],
+      publishedTime: page.createdAt,
+      modifiedTime: page.updatedAt,
+      type: 'article'
+    }
+  };
+}
+
+export default async function Page({ params }: { params: { page: string } }) {
+  const page = await getPage(params.page);
+
+  if (!page) return notFound();
+
+  return (
+    <>
+      <h1 className="mb-8 text-5xl font-bold">{page.title}</h1>
+      <Prose className="mb-8" html={page.body as string} />
+      <p className="text-sm italic">
+        {`This document was last updated on ${new Intl.DateTimeFormat(undefined, {
+          year: 'numeric',
+          month: 'long',
+          day: 'numeric'
+        }).format(new Date(page.updatedAt))}.`}
+      </p>
+    </>
+  );
+}