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.

.gitignore

@@ -1,39 +1,38 @@
+# See https://help.github.com/articles/ignoring-files/ for more about ignoring files.
+
 # dependencies
-node_modules
-.pnp
+/node_modules
+/.pnp
 .pnp.js
-.pnpm-debug.log
 
 # testing
-coverage
+/coverage
+.playwright
 
 # next.js
-.next
-out
+/.next/
+/out/
 
 # production
-build
-dist
+/build
 
 # misc
 .DS_Store
 *.pem
-.idea
 
 # debug
 npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
+.pnpm-debug.log*
 
 # local env files
-.env
-.env.local
-.env.development.local
-.env.test.local
-.env.production.local
+.env*
+!.env.example
 
 # vercel
 .vercel
 
-# Turborepo
-.turbo
+# typescript
+*.tsbuildinfo
+next-env.d.ts