feat: standardise all services to using `services.skynet."${name}";` format

applications/email.nix

@@ -6,7 +6,8 @@
   ...
 }:
 with lib; let
-  cfg = config.services.skynet_email;
+  name = "email";
+  cfg = config.services.skynet."${name}";
 
   # create teh new strings
   create_filter_array = map (x: "(memberOf=cn=${x},ou=groups,${cfg.ldap.base})");
@@ -128,7 +129,7 @@ in {
     ../config/users.nix
   ];
 
-  options.services.skynet_email = {
+  options.services.skynet."${name}" = {
     # options that need to be passed in to make this work
 
     enable = mkEnableOption "Skynet Email";