SFCC provider (#727)

* new SFCC provider

* add search

* normalization + search

* categories as search results

* adress PR feedback

* Update README.md

* get all paths for SSG

* product variants and options

* Apply suggestions from code review

Co-authored-by: Luis Alvarez D. <luis@vercel.com>

* remove console log

* prettier

* clean console log

* ran prettier

* Updated readme

* remove static data and revert config changes

* set default site

Co-authored-by: Luis Alvarez D. <luis@vercel.com>

packages/sfcc/src/api/utils/fetch-local.ts

@@ -0,0 +1,34 @@
+import { FetcherError } from '@vercel/commerce/utils/errors'
+import type { GraphQLFetcher } from '@vercel/commerce/api'
+import type { SFCCConfig } from '../index'
+import fetch from './fetch'
+
+const fetchGraphqlApi: (getConfig: () => SFCCConfig) => GraphQLFetcher =
+  (getConfig) =>
+  async (query: string, { variables, preview } = {}, fetchOptions) => {
+    const config = getConfig()
+    const res = await fetch(config.commerceUrl, {
+      ...fetchOptions,
+      method: 'POST',
+      headers: {
+        ...fetchOptions?.headers,
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify({
+        query,
+        variables,
+      }),
+    })
+
+    const json = await res.json()
+    if (json.errors) {
+      throw new FetcherError({
+        errors: json.errors ?? [{ message: 'Failed to fetch for API' }],
+        status: res.status,
+      })
+    }
+
+    return { data: json.data, res }
+  }
+
+export default fetchGraphqlApi