fix synthing

hosts/freun-dev/services.nix

@@ -141,6 +141,7 @@ in
       enable = true;
       subdomain = "sync";
       dataDir = syncthingDataDir;
+      configDir = "/var/lib/syncthing";
     };
 
     tailscale.enable = true;

modules/services/syncthing.nix

@@ -27,5 +27,14 @@ in
         vHosts.${fqdn}.locations."/".proxyPort = cfg.port;
       };
     };
+
+    systemd.services.syncthing.serviceConfig =
+      lib.mkIf
+        (
+          cfg.dataDir == "/var/lib/syncthing" || cfg.dataDir == null || cfg.configDir == "/var/lib/syncthing"
+        )
+        {
+          StateDirectory = "syncthing";
+        };
   };
 }