Add Open WebUI desktop entry; enable in home

- Move openWebUI.enable from system-modules to home‑modules for desktop
  and laptop hosts
- Remove flatpak entry for OpenWebUI
- Add XDG desktop entry and bind Super‑Ctrl‑O to launch it via dex
- Update Helium appimage to version 0.14.2.1 with new checksum

hosts/default/home-modules.nix

@@ -75,6 +75,7 @@ _: {
       claude.enable = false; # Claude: a large language model
       glance.enable = false; # Glance: my home server dashboard
       jellyfinClient.enable = false; # Jellyfin: My Jellyfin
+      openWebUI.enable = false; # Open WebUI: Comprehensive suite for LLMs with a user-friendly WebUI
     };
   };
 

hosts/default/system-modules.nix

@@ -12,7 +12,6 @@ _: {
       flatseal.enable = false; # Flatpak permissions manager
       upscaler.enable = false; # Upscaler: Upscale and enhance images
       arduino.enable = false; # Arduino: Open-source electronics prototyping platform
-      openWebUI.enable = false; # Open WebUI: Comprehensive suite for LLMs with a user-friendly WebUI
     };
   };