Initial FrameAssistant baseline from the vrdashboard template

Template stripped to the overlay platform (examples, demo UI and Frame
test package removed), renamed to FrameAssistant, and working rules for
the project recorded in CLAUDE.md.

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

docker/cross-arm64.Dockerfile

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+# Cross-compilation environment: x86_64 host tools + aarch64 target libraries via Debian
+# multiarch. The compiler runs natively (no QEMU); Qt's host tools (moc, rcc, qmlcachegen …)
+# are the amd64 builds, target Qt libraries are the arm64 builds.
+FROM debian:trixie
+
+ENV LANG=C.UTF-8
+
+RUN dpkg --add-architecture arm64 \
+ && apt-get update \
+ && apt-get install -y --no-install-recommends \
+        ca-certificates cmake ninja-build pkgconf file patchelf \
+        g++-aarch64-linux-gnu binutils-aarch64-linux-gnu \
+        qt6-base-dev qt6-base-dev-tools qt6-declarative-dev qt6-declarative-dev-tools \
+        qt6-base-dev:arm64 qt6-declarative-dev:arm64 \
+        libgl-dev:arm64 libegl-dev:arm64 libvulkan-dev:arm64 libxkbcommon-dev:arm64 \
+        qml6-module-qtquick:arm64 qml6-module-qtquick-controls:arm64 \
+        qml6-module-qtquick-layouts:arm64 qml6-module-qtquick-templates:arm64 \
+        qml6-module-qtqml-workerscript:arm64 qml6-module-qtquick-window:arm64 \
+        qt6-qpa-plugins:arm64 qt6-wayland:arm64 \
+ && rm -rf /var/lib/apt/lists/*

docker/native.Dockerfile

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+# Native build environment (any architecture): builds for the machine the container runs on.
+# On the Steam Frame (aarch64) this produces the same self-contained bundle as the x86_64 →
+# aarch64 cross build, without needing a cross toolchain.
+FROM debian:trixie
+
+ENV LANG=C.UTF-8
+
+RUN apt-get update \
+ && apt-get install -y --no-install-recommends \
+        ca-certificates cmake ninja-build pkgconf file patchelf g++ \
+        qt6-base-dev qt6-base-dev-tools qt6-declarative-dev qt6-declarative-dev-tools \
+        libgl-dev libegl-dev libvulkan-dev libxkbcommon-dev \
+        qml6-module-qtquick qml6-module-qtquick-controls qml6-module-qtquick-layouts \
+        qml6-module-qtquick-templates qml6-module-qtqml-workerscript qml6-module-qtquick-window \
+        qml6-module-qttest qt6-qpa-plugins qt6-wayland \
+ && rm -rf /var/lib/apt/lists/*

docker/test.Dockerfile

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+# Test environment on top of docker/native.Dockerfile: Mesa Vulkan/GL drivers (incl. the
+# lavapipe software rasterizer), Khronos validation layers and Xvfb. See scripts/container-test.sh.
+FROM frameassistant-build-native
+
+RUN apt-get update \
+ && apt-get install -y --no-install-recommends \
+        mesa-vulkan-drivers vulkan-validationlayers vulkan-tools libgl1-mesa-dri \
+        xvfb xauth fonts-dejavu-core \
+ && rm -rf /var/lib/apt/lists/*