Handle checkout for logged in users (#405)

* create a jwt token if there is a customerId, move the get customer id to the main utils folder.  Need to add in more value to the env file.  Updated the env sample.

* remove yarn.lock and tsconfig.json

* remove build settings

* remove build settings

* remove build settings

* Update tsconfig.json

* Delete package-lock.json

* fix typescript errors

* Update tsconfig.json

Co-authored-by: George Fitzgibbons <george.fitzgibbons@c02zw1aqlvdn.lan>

framework/bigcommerce/api/utils/get-customer-id.ts

@@ -0,0 +1,32 @@
+import type { GetCustomerIdQuery } from '../../schema'
+import type { BigcommerceConfig } from '../'
+
+export const getCustomerIdQuery = /* GraphQL */ `
+  query getCustomerId {
+    customer {
+      entityId
+    }
+  }
+`
+
+async function getCustomerId({
+  customerToken,
+  config,
+}: {
+  customerToken: string
+  config: BigcommerceConfig
+}): Promise<string | undefined> {
+  const { data } = await config.fetch<GetCustomerIdQuery>(
+    getCustomerIdQuery,
+    undefined,
+    {
+      headers: {
+        cookie: `${config.customerCookie}=${customerToken}`,
+      },
+    }
+  )
+
+  return String(data?.customer?.entityId)
+}
+
+export default getCustomerId