dnscms: version image URLs by file hash so media can be cached as immutable

README.md

@@ -59,14 +59,21 @@ not in any repo:
 
 - `Caddyfile`, `default_redirect_503.caddy`: Coolify's own.
 - `studentfestivalen-redirects.caddy`: `studentfestivalen.no` and `studioweb.no` → `neuf.no/studio`.
-- `cms-neuf-no.subdirectives`:
+- `cms-neuf-no.subdirectives`. The GraphQL API versions image URLs with `?v=<file hash>`
+  (`CustomImage.versioned_url`), so those are cached forever. Anything else under `/media/`
+  (admin previews, renditions, old links) is revalidated on every use, instead of browsers
+  guessing a lifetime from `Last-Modified`. `neuf-no.subdirectives` repeats the same headers:
 
   ```caddy
   rewrite / /admin/
 
   handle_path /media/* {
-  	root * /site/cms.neuf.no/media
-  	file_server
+      root * /site/cms.neuf.no/media
+      @versioned query v=*
+      header @versioned Cache-Control "public, max-age=31536000, immutable"
+      @unversioned not query v=*
+      header @unversioned Cache-Control "no-cache"
+      file_server
   }
   ```
 
@@ -75,8 +82,12 @@ not in any repo:
 
   ```caddy
   handle_path /media/* {
-          root * /site/cms.neuf.no/media
-          file_server
+      root * /site/cms.neuf.no/media
+      @versioned query v=*
+      header @versioned Cache-Control "public, max-age=31536000, immutable"
+      @unversioned not query v=*
+      header @unversioned Cache-Control "no-cache"
+      file_server
   }
 
   @pages not path /_next/static/* /_next/image* /assets/* /media/*