feat(attic): extract attic to service module, add cache host, configure reverse proxy/DNS

flake.nix

@@ -47,6 +47,7 @@
       Ingress.modules       = [ ./hosts/Ingress       ];
       Gitea.modules         = [ ./hosts/Gitea         ];
       Vaultwarden.modules   = [ ./hosts/Vaultwarden   ];
+      BinaryCache.modules   = [ ./hosts/BinaryCache   ];
 
       # Production multi-service
       Binnenpost.modules    = [ ./hosts/Binnenpost    ];