Fix pale Wi-Fi/Bluetooth tray icons, das-panel-icon help, publisher and deployer (0.9.5)

- Light theme uses Papirus-Light: the panel icons of Papirus are #dfdfdf,
  made for dark panels (xsettings, theme index, login screen).
- das-panel-icon help/-h/--help print usage instead of setting an icon;
  unknown options are rejected.
- New packages publisher (publish) and deployer (deploy) on the desktop
  image: config in ~/.config/<name>/ (neutral example copied on first run),
  history in ~/.local/state/<name>/.
- das-theme 0.3.0, das-settings 0.6.0.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

srcpkgs/das-settings/files/bin/das-panel-icon

@@ -2,12 +2,25 @@
 # Picks the icon of the menu button on the panel: das-panel-icon star|trident|<icon name>.
 set -u
 
+usage() {
+  echo "usage: das-panel-icon star|trident|ICON-NAME" >&2
+  echo "now: $(xfconf-query -c xfce4-panel -p /plugins/plugin-1/button-icon 2>/dev/null || echo das-logo)" >&2
+}
+
 case ${1:-} in
 star) icon=das-logo ;;
 trident) icon=das-trident ;;
+help | -h | --help)
+  usage
+  exit 0
+  ;;
 "")
-  echo "usage: das-panel-icon star|trident|ICON-NAME" >&2
-  echo "now: $(xfconf-query -c xfce4-panel -p /plugins/plugin-1/button-icon 2>/dev/null || echo das-logo)" >&2
+  usage
+  exit 1
+  ;;
+-*)
+  echo "das-panel-icon: unknown option $1" >&2
+  usage
   exit 1
   ;;
 *) icon=$1 ;;