home-manager/programs/nushell: init extension module

modules/home-manager/default.nix

@@ -4,6 +4,7 @@
     ./programs/pipewire.nix
     ./programs/pop-launcher.nix
     ./programs/borgmatic.nix
+    ./programs/nushell.nix
     ./programs/python.nix
     ./services/archivebox.nix
     ./services/borgbackup.nix

modules/home-manager/programs/nushell.nix

@@ -0,0 +1,15 @@
+# This is just an extended implementation of exporting Nushell session
+# variables since the one from home-manager is only in POSIX sh script.
+{ config, lib, pkgs, ... }:
+
+let
+  cfg = config.programs.nushell;
+in
+{
+  config.programs.nushell.extraEnv = let
+    exportSessionVariables = lib.mapAttrs (n: v:
+      "$env.${n} = ${v}") config.home.sessionVariables;
+  in lib.mkBefore ''
+    ${exportSessionVariables}
+  '';
+}