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/publisher/files/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Das
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.