fixes issues with docs generation

modules/blocks/authelia.nix

@@ -14,7 +14,7 @@ in
     subdomain = lib.mkOption {
       type = lib.types.str;
       description = "Subdomain under which Authelia will be served.";
-      example = "ha";
+      example = "auth";
     };
 
     domain = lib.mkOption {
@@ -36,9 +36,17 @@ in
     };
 
     autheliaUser = lib.mkOption {
-      type = lib.types.str;
-      description = "System user for this Authelia instance";
-      default = "authelia_" + builtins.replaceStrings ["-" "."] ["_" "_"] fqdn;
+      type = lib.types.nullOr lib.types.str;
+      description = ''System user for this Authelia instance.
+
+If set to null, defaults to:
+<programlisting language="nix">
+"authelia_" +
+  (builtins.replaceStrings ["-" "."] ["_" "_"]
+    ''${shb.authelia.subdomain}.''${shb.authelia.domain}")
+</programlisting>
+'';
+      default = null;
     };
 
     secrets = lib.mkOption {
@@ -112,7 +120,7 @@ in
 
     services.authelia.instances.${fqdn} = {
       enable = true;
-      user = cfg.autheliaUser;
+      user = cfg.autheliaUser or "authelia_" + builtins.replaceStrings ["-" "."] ["_" "_"] fqdn;
 
       secrets = {
         inherit (cfg.secrets) jwtSecretFile storageEncryptionKeyFile;

modules/blocks/postgresql.nix

@@ -6,7 +6,7 @@ in
   options.shb.postgresql = {
     debug = lib.mkOption {
       type = lib.types.bool;
-      description = lib.mdDocs ''
+      description = lib.mdDoc ''
       Enable debugging options.
 
       Currently enables shared_preload_libraries = "auto_explain, pg_stat_statements"

modules/blocks/vpn.nix

@@ -211,7 +211,7 @@ in
 
           provider = lib.mkOption {
             description = lib.mdDoc "VPN provider, if given uses ready-made configuration.";
-            type = lib.types.nullOf (lib.types.enum [ "nordvpn" ]);
+            type = lib.types.nullOr (lib.types.enum [ "nordvpn" ]);
             default = null;
           };