hosts/ni/services/backup: update Disko and snapper config

configs/nixos/ni/disko.nix

@@ -60,6 +60,16 @@
                     mountpoint = "/gnu";
                   };
                 })
+
+                (lib.mkIf (config.services.snapper.configs != {}) {
+                  "/home/.snapshots" = {
+                    mountOptions = [ "compress=zstd" ];
+                  };
+
+                  "/.snapshots" = {
+                    mountOptions = [ "compress=zstd" ];
+                  };
+                })
               ];
             };
           };

configs/nixos/ni/modules/services/backup/default.nix

@@ -124,6 +124,14 @@ in {
           TIMELINE_LIMIT_WEEKLY = 12;
         };
       };
+
+      filters = ''
+        /tmp
+        /var/tmp
+        /var/log
+        /var/lib/libvirt/images
+        /srv
+      '';
     };
   };
 }