feat(cli): prepare nextjs starter template for live mode (#7633)

Co-authored-by: Espen Hovlandsdal <[email protected]>

packages/@sanity/cli/src/actions/init-project/templates/nextjs/index.ts

@@ -165,6 +165,21 @@ export const client = createClient({
 })
 `
 
+const live = `// Querying with "sanityFetch" will keep content automatically updated
+// Before using it, import and render "<SanityLive />" in your layout, see
+// https://github.com/sanity-io/next-sanity#live-content-api for more information.
+import { defineLive } from "next-sanity";
+import { client } from './client'
+
+export const { sanityFetch, SanityLive } = defineLive({ 
+  client: client.withConfig({ 
+    // Live content is currently only available on the experimental API
+    // https://www.sanity.io/docs/api-versioning
+    apiVersion: 'vX' 
+  }) 
+});
+`
+
 const imageTS = `import createImageUrlBuilder from '@sanity/image-url'
 import { SanityImageSource } from "@sanity/image-url/lib/types/types";
 
@@ -201,6 +216,7 @@ export const sanityFolder = (
     'env.': useTypeScript ? envTS : envJS,
     'lib': {
       'client.': client,
+      'live.': live,
       'image.': useTypeScript ? imageTS : imageJS,
     },
   }