refactor(binds): app launcher is SUPER+Space only

Drop the duplicate SUPER+D drun bind; menu Apps hint shows SUPER+Space.

modules/home/rofi.nix

@@ -19,7 +19,7 @@ let
   rasiOverride = cfg.themesDir + "/${t.slug}/rofi.rasi";
   hasRasiOverride = builtins.pathExists rasiOverride;
 
-  # App-launcher theme (SUPER+Space/D → `rofi -show drun -theme launcher`).
+  # App-launcher theme (SUPER+Space → `rofi -show drun -theme launcher`).
   # Kept separate from the base theme so a theme can give the launcher its
   # own layout (e.g. Boreal's icon grid) WITHOUT that layout leaking into
   # the text menus, which share the base theme and need a list. The default