fix(niri): drop the bar toggle keybind

Alt+W switched between quickshell and Waybar. Quickshell owns the bar now, so
the branch back was already dead: it calls moonarch-waybar, which no longer
exists. Pressing it killed the bar with nothing to restore it.

defaults/xdg/niri/config.kdl

@@ -148,8 +148,6 @@ binds {
 
     Super+C hotkey-overlay-title="Clipboard History: quickshell popout" { spawn "qs" "-c" "moonarch" "ipc" "call" "popout" "toggle" "clipboard"; }
 
-    Alt+W hotkey-overlay-title="Toggle bar: quickshell / Waybar" { spawn-sh "if pkill -x quickshell; then moonarch-waybar & else killall waybar; quickshell -c moonarch & fi"; }
-
     Super+E { spawn-sh "xdg-open ~"; }