home: zsh: use absolute path to 'XDG_CONFIG_HOME'

The path handling has been fixed upstream, which makes this module more
readable.

flake.lock

@@ -73,11 +73,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1751413152,
-        "narHash": "sha256-Tyw1RjYEsp5scoigs1384gIg6e0GoBVjms4aXFfRssQ=",
+        "lastModified": 1753121425,
+        "narHash": "sha256-TVcTNvOeWWk1DXljFxVRp+E0tzG1LhrVjOGGoMHuXio=",
         "owner": "hercules-ci",
         "repo": "flake-parts",
-        "rev": "77826244401ea9de6e3bac47c2db46005e1f30b5",
+        "rev": "644e0fc48951a860279da645ba77fe4a6e814c5e",
         "type": "github"
       },
       "original": {
@@ -159,11 +159,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1752467539,
-        "narHash": "sha256-4kaR+xmng9YPASckfvIgl5flF/1nAZOplM+Wp9I5SMI=",
+        "lastModified": 1753617834,
+        "narHash": "sha256-WEVfKrdIdu5CpppJ0Va3vzP0DKlS+ZTLbBjugMO2Drg=",
         "owner": "nix-community",
         "repo": "home-manager",
-        "rev": "1e54837569e0b80797c47be4720fab19e0db1616",
+        "rev": "72cc1e3134a35005006f06640724319caa424737",
         "type": "github"
       },
       "original": {
@@ -175,11 +175,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1752644555,
-        "narHash": "sha256-oeRcp4VEyZ/3ZgfRRoq60/08l2zy0K53l8MdfSIYd24=",
+        "lastModified": 1753429684,
+        "narHash": "sha256-9h7+4/53cSfQ/uA3pSvCaBepmZaz/dLlLVJnbQ+SJjk=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "9100a4f6bf446603b9575927c8585162f9ec9aa6",
+        "rev": "7fd36ee82c0275fb545775cc5e4d30542899511d",
         "type": "github"
       },
       "original": {

modules/home/zsh/default.nix

@@ -1,14 +1,6 @@
 { config, pkgs, lib, ... }:
 let
   cfg = config.my.home.zsh;
-
-  # Have a nice relative path for XDG_CONFIG_HOME, without leading `/`
-  relativeXdgConfig =
-    let
-      noHome = lib.removePrefix config.home.homeDirectory;
-      noSlash = lib.removePrefix "/";
-    in
-    noSlash (noHome config.xdg.configHome);
 in
 {
   options.my.home.zsh = with lib; {
@@ -57,7 +49,7 @@ in
 
       programs.zsh = {
         enable = true;
-        dotDir = "${relativeXdgConfig}/zsh"; # Don't clutter $HOME
+        dotDir = "${config.xdg.configHome}/zsh"; # Don't clutter $HOME
         enableCompletion = true;
 
         history = {