servo: vpn services are part of 'wireguard-wg0'

this makes it so if we restart the wireguard connection, the services
themeselves _also_ restart. that should avoid leaving any of them in an
orphaned namespace

hosts/servo/services/jackett.nix

@@ -8,6 +8,7 @@
   services.jackett.enable = true;
 
   systemd.services.jackett.after = [ "wireguard-wg0.service" ];
+  systemd.services.jackett.partOf = [ "wireguard-wg0.service" ];
   systemd.services.jackett.serviceConfig = {
     # run this behind the OVPN static VPN
     NetworkNamespacePath = "/run/netns/ovpns";

hosts/servo/services/postfix.nix

@@ -65,6 +65,7 @@ in
   services.postfix.submissionsOptions = submissionOptions;
 
   systemd.services.postfix.after = [ "wireguard-wg0.service" ];
+  systemd.services.postfix.partOf = [ "wireguard-wg0.service" ];
   systemd.services.postfix.serviceConfig = {
     # run this behind the OVPN static VPN
     NetworkNamespacePath = "/run/netns/ovpns";
@@ -86,6 +87,7 @@ in
   services.opendkim.selector = "mx";
 
   systemd.services.opendkim.after = [ "wireguard-wg0.service" ];
+  systemd.services.opendkim.partOf = [ "wireguard-wg0.service" ];
   systemd.services.opendkim.serviceConfig = {
     # run this behind the OVPN static VPN
     NetworkNamespacePath = "/run/netns/ovpns";

hosts/servo/services/transmission.nix

@@ -41,6 +41,7 @@
   services.transmission.downloadDirPermissions = "775";
 
   systemd.services.transmission.after = [ "wireguard-wg0.service" ];
+  systemd.services.transmission.partOf = [ "wireguard-wg0.service" ];
   systemd.services.transmission.serviceConfig = {
     # run this behind the OVPN static VPN
     NetworkNamespacePath = "/run/netns/ovpns";