replace the rofi control centre with a real GTK panel

rofi spawns a process per menu, so every volume nudge and every step back
destroyed and recreated the window. That is the flicker, and no tuning fixes
it. The panel is now one GTK window: a GtkStack for views, real GtkScale
sliders wired to wpctl, status on a timer, and a pidfile so super+x toggles
it shut. Escape steps back inside the same window.

Also: picom no longer fades or animates rofi, ::selection is not valid GTK
css, and the network/bluetooth lists no longer print their payload column.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Cn3dHfbgNYdbZvzb1b3GQt

.config/bspwm/sxhkdrc

@@ -1,11 +1,10 @@
 # System binding
-super + {Return,v,w,x,b,period}
+super + {Return,v,w,x,b}
     {st, \
     sh ~/.config/scripts/rofi-menus/clipboard-manager.sh, \
     rofi -show drun, \
-    sh ~/.config/scripts/control-center.sh, \
-    sh ~/.config/scripts/toggle-bar.sh, \
-    sh ~/.config/scripts/rofi-menus/rofimoji.sh}
+    python3 ~/.config/scripts/control-panel.py, \
+    sh ~/.config/scripts/toggle-bar.sh}
 
 # Screenshots
 super + alt + p