feat(dnd): swaync Do-Not-Disturb toggle + Waybar bell indicator

Adds a Do-Not-Disturb story on top of swaync:

- Waybar `custom/notification` module via `swaync-client -swb` — streams
  the notification count + DND state (no polling). Left-click toggles the
  panel, right-click toggles DND; bell-off glyph + muted color when DND is
  on, accent when notifications are waiting.
- `nomarchy-menu dnd` toggle in the root picker and bound to SUPER+CTRL+D
  (so it shows in the SUPER+? cheatsheet). Turning DND off confirms with a
  toast; turning it on is silent — notifications are suppressed and the
  bell-off icon is the cue.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

modules/home/rofi.nix

@@ -164,6 +164,14 @@ let
         [ -n "$q" ] || exit 0
         exec ${cfg.terminal} -e npx --yes @anthropic-ai/claude-code@latest "$q" ;;
 
+      dnd)
+        # Toggle swaync Do-Not-Disturb (-d prints the new state). With DND
+        # on, notifications are suppressed — the Waybar bell-off icon is the
+        # cue — so only confirm with a toast when turning it back off.
+        [ "$(swaync-client -d)" = "false" ] \
+          && notify-send "Do Not Disturb off" "Notifications resumed."
+        exit 0 ;;
+
       "")
         entries=(
           "󰀻  Apps"
@@ -178,6 +186,7 @@ let
           "󰄄  Capture"
           "󰋖  Keybindings"
           "󰭹  Ask Claude"
+          "󰂛  Do Not Disturb"
         )
         # Power-profile picker only when this is a laptop (battery present)
         # running power-profiles-daemon — matches the Waybar indicator's
@@ -201,12 +210,13 @@ let
           *Capture*)   exec "$0" capture ;;
           *Keybindings*) exec "$0" keybinds ;;
           *Ask*)       exec "$0" ask ;;
+          *"Do Not Disturb"*) exec "$0" dnd ;;
           *"Power profile"*) exec "$0" power-profile ;;
           *Power*)     exec "$0" power ;;
         esac ;;
 
       *)
-        echo "usage: nomarchy-menu [power|power-profile|theme|clipboard|calc|files|emoji|web|network|bluetooth|capture|keybinds|ask]" >&2
+        echo "usage: nomarchy-menu [power|power-profile|theme|clipboard|calc|files|emoji|web|network|bluetooth|capture|keybinds|ask|dnd]" >&2
         exit 64 ;;
     esac
   '';