build(deps): update to Next.js v16 + use image digests instead of tags

Ref:
- https://docs.docker.com/dhi/core-concepts/digests/
- https://github.com/goldbergyoni/nodebestpractices/blob/master/sections/docker/image-tags.md
- https://emmer.dev/blog/what-is-a-docker-digest/

configs/config-tailwind/styles.css

@@ -48,7 +48,7 @@
 
   q,
   blockquote {
-    @apply italic tracking-wider;
+    @apply tracking-wider italic;
   }
   blockquote {
     @apply border-gray-lighter border-l-4 pl-3 italic;