feat(x1): refresh desktop package set

Add metacfg.rag, cider-2, opencode, oversteer and qwen-code; drop
fabric-ai and gemini-cli.

systems/x86_64-linux/x1/default.nix

@@ -90,9 +90,8 @@ with lib.metacfg;
     azure-cli
     claude-code
     claude-desktop-with-fhs
+    metacfg.rag
     desktop-file-utils
-    fabric-ai
-    gemini-cli
     gnome-terminal
     gnome-remote-desktop
     gtypist
@@ -107,6 +106,10 @@ with lib.metacfg;
     tipp10
     uv
     vscode
+    cider-2
+    opencode
+    oversteer
+    qwen-code
   ];
 
   services.ratbagd.enable = true;