feat(s3-revproxy): tune the cache-control

Adopt the original values from the Perl script.

Signed-off-by: Raito Bezarius <masterancpp@gmail.com>

services/s3-revproxy/default.nix

@@ -122,6 +122,16 @@ in
             allowMethods = [ "GET" ];
             allowOrigins = [ "*" ];
           };
+
+          cache = {
+            noCacheEnabled = false;
+            # Taken from the original Perl script.
+            # maxage=600: Serve from cache for 5 minutes.
+            # stale-while-revaliadate=1800: Serve from cache while updating in the background for 30 minutes.
+            # https://web.dev/stale-while-revalidate/
+            # https://developer.fastly.com/learning/concepts/cache-freshness/
+            cacheControl = "maxage=600,stale-while-revalidate=1800,public";
+          };
         };
         targets = mapAttrs (name: bucket: mkTarget { inherit name bucket; }) cfg.targets;
       };