Phase 3: screenshot hotkeys, clipboard history, Papirus icon theme

Screenshots (PrintScreen / Shift+PrintScreen):
- PrintScreen → full screenshot saved to ~/Pictures via scrot
- Shift+PrintScreen → interactive region select via scrot -s
- Both send a dunst notification on save
- scrot added to packages

Clipboard manager:
- Replace janky PRIMARY/CLIPBOARD sync loop with parcellite
- parcellite provides clipboard history, survives app close,
  shows a tray icon for browsing past entries
- parcellite added to packages

Icon theme:
- Switch from Adwaita to Papirus-Dark across GTK2, GTK3 settings,
  and theme index.theme
- papirus-icon-theme added to packages

Also fix remaining stale sky* references in menu.c (skywallpaper,
pkill skywm) and events.c (skylauncher).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

wm/src/events.c

@@ -286,7 +286,17 @@ void on_key_press(WM *wm, XKeyEvent *e) {
 
     /* Alt+F1 — launcher */
     if ((e->state & Mod1Mask) && sym == XK_F1)
-        system("skylauncher &");
+        system("orionlauncher &");
+
+    /* PrintScreen — full screenshot to ~/Pictures */
+    if (sym == XK_Print) {
+        if (e->state & ShiftMask)
+            system("mkdir -p ~/Pictures && scrot -s ~/Pictures/screenshot_%Y%m%d_%H%M%S.png"
+                   " && notify-send 'Screenshot' 'Region saved to ~/Pictures' &");
+        else
+            system("mkdir -p ~/Pictures && scrot ~/Pictures/screenshot_%Y%m%d_%H%M%S.png"
+                   " && notify-send 'Screenshot' 'Saved to ~/Pictures' &");
+    }
 
     /* Super+Left — snap left */
     if ((e->state & Mod4Mask) && sym == XK_Left && wm->focused)

wm/src/menu.c

@@ -15,10 +15,10 @@ static const MenuItem MENU_ITEMS[] = {
     { "Volume Control",    "pavucontrol &"                              },
     { "Display Settings",  "arandr &"                                   },
     { "──────────────────", NULL                                         },
-    { "Change Wallpaper",  "skywallpaper --reset &"                     },
+    { "Change Wallpaper",  "orionwallpaper --reset &"                    },
     { "──────────────────", NULL                                         },
-    { "Restart OrionWM",     "pkill skywm; sleep 0.2; skywm &"           },
-    { "Quit OrionOS",        "pkill skywm"                                },
+    { "Restart OrionWM",   "pkill orionwm; sleep 0.2; orionwm &"        },
+    { "Quit OrionOS",      "pkill orionwm"                              },
 };
 #define MENU_COUNT  ((int)(sizeof(MENU_ITEMS) / sizeof(MENU_ITEMS[0])))