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>

docker/builder/Dockerfile

@@ -0,0 +1,17 @@
+# Build environment for Das OS packages and ISO images.
+#
+# Void Linux base on purpose (not Alpine): xbps-src and void-mklive need xbps,
+# and packages must be built against the same glibc they ship with.
+FROM ghcr.io/void-linux/void-glibc-full:latest
+
+RUN xbps-install -Syu xbps \
+    && xbps-install -yu \
+    && xbps-install -y bash dosfstools e2fsprogs git librsvg-utils sudo \
+    && xbps-remove -Oy
+
+# Pinned so ISO builds do not change under us; bump deliberately.
+ARG MKLIVE_COMMIT=8ca31d1
+RUN git clone https://github.com/void-linux/void-mklive /opt/void-mklive \
+    && git -C /opt/void-mklive checkout --quiet "$MKLIVE_COMMIT"
+
+WORKDIR /work