Add postgresql (#163)

* feat: add postgresql

* feat: add grafana dashbaord, fix exporter

secrets/nixos.nix

@@ -248,10 +248,15 @@ in {
 
       (mkIf cfg.server.webserver.enable {
         age.secrets = {
-          "certs/ecc-server.key" = {
+          "caddy-ecc-server.key" = {
             file = "${mysecrets}/certs/ecc-server.key.age";
             mode = "0400";
-            owner = "caddy"; # used by caddy only
+            owner = "caddy";
+          };
+          "postgres-ecc-server.key" = {
+            file = "${mysecrets}/certs/ecc-server.key.age";
+            mode = "0400";
+            owner = "postgres";
           };
         };
       })