Replace telegraf with node exporter

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

hosts/jupiter-vps/format.nix

@@ -26,10 +26,22 @@
             name = "root";
             size = "100%";
             content = {
-              type = "filesystem";
-              format = "ext4";
-              mountpoint = "/";
-              mountOptions = [ "defaults" ];
+              type = "btrfs";
+              extraArgs = [ "-f" ];
+              subvolumes =
+                let
+                  mountOptions = [
+                    "compress=zstd:1"
+                    "noatime"
+                    "user_subvol_rm_allowed"
+                  ];
+                in
+                {
+                  "@" = {
+                    mountpoint = "/";
+                    inherit mountOptions;
+                  };
+                };
             };
           };
         };