Initial Das OS 0.1.0: Void Linux live ISO with Xfce

- xbps-src templates: das-theme (adw-gtk3-based GTK themes, generated
  xfwm4 frames, wallpapers, logo), das-settings (Xfce, panel, LightDM
  defaults in /etc/xdg/das), adw-gtk3 and font-jetbrains-mono
- void-mklive profile in live/: packages, runit services, rootfs overlay,
  Ukrainian locale, live user with autologin
- Void builder container, build scripts, QEMU runner and Makefile
- Bilingual README with screenshots

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

srcpkgs/das-settings/files/xfconf/xfce4-desktop.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!-- Wallpapers are keyed by monitor connector name, so das-session-init sets them at first login. -->
+<channel name="xfce4-desktop" version="1.0">
+  <property name="backdrop" type="empty">
+    <property name="single-workspace-mode" type="bool" value="true"/>
+    <property name="single-workspace-number" type="int" value="0"/>
+  </property>
+  <property name="desktop-icons" type="empty">
+    <property name="icon-size" type="uint" value="48"/>
+    <property name="file-icons" type="empty">
+      <property name="show-filesystem" type="bool" value="false"/>
+      <property name="show-home" type="bool" value="true"/>
+      <property name="show-removable" type="bool" value="true"/>
+      <property name="show-trash" type="bool" value="true"/>
+    </property>
+  </property>
+</channel>